Attr.java revision 2571:10fc81ac75b4
1/* 2 * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package com.sun.tools.javac.comp; 27 28import java.util.*; 29 30import javax.lang.model.element.ElementKind; 31import javax.tools.JavaFileObject; 32 33import com.sun.source.tree.IdentifierTree; 34import com.sun.source.tree.MemberReferenceTree.ReferenceMode; 35import com.sun.source.tree.MemberSelectTree; 36import com.sun.source.tree.TreeVisitor; 37import com.sun.source.util.SimpleTreeVisitor; 38import com.sun.tools.javac.code.*; 39import com.sun.tools.javac.code.Lint.LintCategory; 40import com.sun.tools.javac.code.Scope.WriteableScope; 41import com.sun.tools.javac.code.Symbol.*; 42import com.sun.tools.javac.code.Type.*; 43import com.sun.tools.javac.comp.Check.CheckContext; 44import com.sun.tools.javac.comp.DeferredAttr.AttrMode; 45import com.sun.tools.javac.comp.Infer.InferenceContext; 46import com.sun.tools.javac.comp.Infer.FreeTypeListener; 47import com.sun.tools.javac.jvm.*; 48import com.sun.tools.javac.tree.*; 49import com.sun.tools.javac.tree.JCTree.*; 50import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; 51import com.sun.tools.javac.util.*; 52import com.sun.tools.javac.util.Dependencies.AttributionKind; 53import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 54import com.sun.tools.javac.util.List; 55import static com.sun.tools.javac.code.Flags.*; 56import static com.sun.tools.javac.code.Flags.ANNOTATION; 57import static com.sun.tools.javac.code.Flags.BLOCK; 58import static com.sun.tools.javac.code.Kinds.*; 59import static com.sun.tools.javac.code.Kinds.ERRONEOUS; 60import static com.sun.tools.javac.code.TypeTag.*; 61import static com.sun.tools.javac.code.TypeTag.WILDCARD; 62import static com.sun.tools.javac.tree.JCTree.Tag.*; 63 64/** This is the main context-dependent analysis phase in GJC. It 65 * encompasses name resolution, type checking and constant folding as 66 * subtasks. Some subtasks involve auxiliary classes. 67 * @see Check 68 * @see Resolve 69 * @see ConstFold 70 * @see Infer 71 * 72 * <p><b>This is NOT part of any supported API. 73 * If you write code that depends on this, you do so at your own risk. 74 * This code and its internal interfaces are subject to change or 75 * deletion without notice.</b> 76 */ 77public class Attr extends JCTree.Visitor { 78 protected static final Context.Key<Attr> attrKey = new Context.Key<>(); 79 80 final Names names; 81 final Log log; 82 final Symtab syms; 83 final Resolve rs; 84 final Infer infer; 85 final DeferredAttr deferredAttr; 86 final Check chk; 87 final Flow flow; 88 final MemberEnter memberEnter; 89 final TreeMaker make; 90 final ConstFold cfolder; 91 final Enter enter; 92 final Target target; 93 final Types types; 94 final JCDiagnostic.Factory diags; 95 final Annotate annotate; 96 final DeferredLintHandler deferredLintHandler; 97 final TypeEnvs typeEnvs; 98 final Dependencies dependencies; 99 100 public static Attr instance(Context context) { 101 Attr instance = context.get(attrKey); 102 if (instance == null) 103 instance = new Attr(context); 104 return instance; 105 } 106 107 protected Attr(Context context) { 108 context.put(attrKey, this); 109 110 names = Names.instance(context); 111 log = Log.instance(context); 112 syms = Symtab.instance(context); 113 rs = Resolve.instance(context); 114 chk = Check.instance(context); 115 flow = Flow.instance(context); 116 memberEnter = MemberEnter.instance(context); 117 make = TreeMaker.instance(context); 118 enter = Enter.instance(context); 119 infer = Infer.instance(context); 120 deferredAttr = DeferredAttr.instance(context); 121 cfolder = ConstFold.instance(context); 122 target = Target.instance(context); 123 types = Types.instance(context); 124 diags = JCDiagnostic.Factory.instance(context); 125 annotate = Annotate.instance(context); 126 deferredLintHandler = DeferredLintHandler.instance(context); 127 typeEnvs = TypeEnvs.instance(context); 128 dependencies = Dependencies.instance(context); 129 130 Options options = Options.instance(context); 131 132 Source source = Source.instance(context); 133 allowStringsInSwitch = source.allowStringsInSwitch(); 134 allowPoly = source.allowPoly(); 135 allowTypeAnnos = source.allowTypeAnnotations(); 136 allowLambda = source.allowLambda(); 137 allowDefaultMethods = source.allowDefaultMethods(); 138 allowStaticInterfaceMethods = source.allowStaticInterfaceMethods(); 139 sourceName = source.name; 140 relax = (options.isSet("-retrofit") || 141 options.isSet("-relax")); 142 findDiamonds = options.get("findDiamond") != null && 143 source.allowDiamond(); 144 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning"); 145 identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false); 146 147 statInfo = new ResultInfo(NIL, Type.noType); 148 varInfo = new ResultInfo(VAR, Type.noType); 149 unknownExprInfo = new ResultInfo(VAL, Type.noType); 150 unknownAnyPolyInfo = new ResultInfo(VAL, Infer.anyPoly); 151 unknownTypeInfo = new ResultInfo(TYP, Type.noType); 152 unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType); 153 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext); 154 } 155 156 /** Switch: relax some constraints for retrofit mode. 157 */ 158 boolean relax; 159 160 /** Switch: support target-typing inference 161 */ 162 boolean allowPoly; 163 164 /** Switch: support type annotations. 165 */ 166 boolean allowTypeAnnos; 167 168 /** Switch: support lambda expressions ? 169 */ 170 boolean allowLambda; 171 172 /** Switch: support default methods ? 173 */ 174 boolean allowDefaultMethods; 175 176 /** Switch: static interface methods enabled? 177 */ 178 boolean allowStaticInterfaceMethods; 179 180 /** Switch: generates a warning if diamond can be safely applied 181 * to a given new expression 182 */ 183 boolean findDiamonds; 184 185 /** 186 * Internally enables/disables diamond finder feature 187 */ 188 static final boolean allowDiamondFinder = true; 189 190 /** 191 * Switch: warn about use of variable before declaration? 192 * RFE: 6425594 193 */ 194 boolean useBeforeDeclarationWarning; 195 196 /** 197 * Switch: generate warnings whenever an anonymous inner class that is convertible 198 * to a lambda expression is found 199 */ 200 boolean identifyLambdaCandidate; 201 202 /** 203 * Switch: allow strings in switch? 204 */ 205 boolean allowStringsInSwitch; 206 207 /** 208 * Switch: name of source level; used for error reporting. 209 */ 210 String sourceName; 211 212 /** Check kind and type of given tree against protokind and prototype. 213 * If check succeeds, store type in tree and return it. 214 * If check fails, store errType in tree and return it. 215 * No checks are performed if the prototype is a method type. 216 * It is not necessary in this case since we know that kind and type 217 * are correct. 218 * 219 * @param tree The tree whose kind and type is checked 220 * @param ownkind The computed kind of the tree 221 * @param resultInfo The expected result of the tree 222 */ 223 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) { 224 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext(); 225 Type owntype; 226 if (!found.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) { 227 if ((ownkind & ~resultInfo.pkind) != 0) { 228 log.error(tree.pos(), "unexpected.type", 229 kindNames(resultInfo.pkind), 230 kindName(ownkind)); 231 owntype = types.createErrorType(found); 232 } else if (allowPoly && inferenceContext.free(found)) { 233 //delay the check if there are inference variables in the found type 234 //this means we are dealing with a partially inferred poly expression 235 owntype = resultInfo.pt; 236 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() { 237 @Override 238 public void typesInferred(InferenceContext inferenceContext) { 239 ResultInfo pendingResult = 240 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt)); 241 check(tree, inferenceContext.asInstType(found), ownkind, pendingResult); 242 } 243 }); 244 } else { 245 owntype = resultInfo.check(tree, found); 246 } 247 } else { 248 owntype = found; 249 } 250 tree.type = owntype; 251 return owntype; 252 } 253 254 /** Is given blank final variable assignable, i.e. in a scope where it 255 * may be assigned to even though it is final? 256 * @param v The blank final variable. 257 * @param env The current environment. 258 */ 259 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) { 260 Symbol owner = env.info.scope.owner; 261 // owner refers to the innermost variable, method or 262 // initializer block declaration at this point. 263 return 264 v.owner == owner 265 || 266 ((owner.name == names.init || // i.e. we are in a constructor 267 owner.kind == VAR || // i.e. we are in a variable initializer 268 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block 269 && 270 v.owner == owner.owner 271 && 272 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env)); 273 } 274 275 /** Check that variable can be assigned to. 276 * @param pos The current source code position. 277 * @param v The assigned varaible 278 * @param base If the variable is referred to in a Select, the part 279 * to the left of the `.', null otherwise. 280 * @param env The current environment. 281 */ 282 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) { 283 if ((v.flags() & FINAL) != 0 && 284 ((v.flags() & HASINIT) != 0 285 || 286 !((base == null || 287 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) && 288 isAssignableAsBlankFinal(v, env)))) { 289 if (v.isResourceVariable()) { //TWR resource 290 log.error(pos, "try.resource.may.not.be.assigned", v); 291 } else { 292 log.error(pos, "cant.assign.val.to.final.var", v); 293 } 294 } 295 } 296 297 /** Does tree represent a static reference to an identifier? 298 * It is assumed that tree is either a SELECT or an IDENT. 299 * We have to weed out selects from non-type names here. 300 * @param tree The candidate tree. 301 */ 302 boolean isStaticReference(JCTree tree) { 303 if (tree.hasTag(SELECT)) { 304 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected); 305 if (lsym == null || lsym.kind != TYP) { 306 return false; 307 } 308 } 309 return true; 310 } 311 312 /** Is this symbol a type? 313 */ 314 static boolean isType(Symbol sym) { 315 return sym != null && sym.kind == TYP; 316 } 317 318 /** The current `this' symbol. 319 * @param env The current environment. 320 */ 321 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) { 322 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this); 323 } 324 325 /** Attribute a parsed identifier. 326 * @param tree Parsed identifier name 327 * @param topLevel The toplevel to use 328 */ 329 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) { 330 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel); 331 localEnv.enclClass = make.ClassDef(make.Modifiers(0), 332 syms.errSymbol.name, 333 null, null, null, null); 334 localEnv.enclClass.sym = syms.errSymbol; 335 return tree.accept(identAttributer, localEnv); 336 } 337 // where 338 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer(); 339 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> { 340 @Override 341 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) { 342 Symbol site = visit(node.getExpression(), env); 343 if (site.kind == ERR || site.kind == ABSENT_TYP) 344 return site; 345 Name name = (Name)node.getIdentifier(); 346 if (site.kind == PCK) { 347 env.toplevel.packge = (PackageSymbol)site; 348 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK); 349 } else { 350 env.enclClass.sym = (ClassSymbol)site; 351 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site); 352 } 353 } 354 355 @Override 356 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) { 357 return rs.findIdent(env, (Name)node.getName(), TYP | PCK); 358 } 359 } 360 361 public Type coerce(Type etype, Type ttype) { 362 return cfolder.coerce(etype, ttype); 363 } 364 365 public Type attribType(JCTree node, TypeSymbol sym) { 366 Env<AttrContext> env = typeEnvs.get(sym); 367 Env<AttrContext> localEnv = env.dup(node, env.info.dup()); 368 return attribTree(node, localEnv, unknownTypeInfo); 369 } 370 371 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) { 372 // Attribute qualifying package or class. 373 JCFieldAccess s = (JCFieldAccess)tree.qualid; 374 return attribTree(s.selected, env, 375 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK), 376 Type.noType)); 377 } 378 379 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) { 380 breakTree = tree; 381 JavaFileObject prev = log.useSource(env.toplevel.sourcefile); 382 try { 383 attribExpr(expr, env); 384 } catch (BreakAttr b) { 385 return b.env; 386 } catch (AssertionError ae) { 387 if (ae.getCause() instanceof BreakAttr) { 388 return ((BreakAttr)(ae.getCause())).env; 389 } else { 390 throw ae; 391 } 392 } finally { 393 breakTree = null; 394 log.useSource(prev); 395 } 396 return env; 397 } 398 399 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) { 400 breakTree = tree; 401 JavaFileObject prev = log.useSource(env.toplevel.sourcefile); 402 try { 403 attribStat(stmt, env); 404 } catch (BreakAttr b) { 405 return b.env; 406 } catch (AssertionError ae) { 407 if (ae.getCause() instanceof BreakAttr) { 408 return ((BreakAttr)(ae.getCause())).env; 409 } else { 410 throw ae; 411 } 412 } finally { 413 breakTree = null; 414 log.useSource(prev); 415 } 416 return env; 417 } 418 419 private JCTree breakTree = null; 420 421 private static class BreakAttr extends RuntimeException { 422 static final long serialVersionUID = -6924771130405446405L; 423 private Env<AttrContext> env; 424 private BreakAttr(Env<AttrContext> env) { 425 this.env = env; 426 } 427 } 428 429 class ResultInfo { 430 final int pkind; 431 final Type pt; 432 final CheckContext checkContext; 433 434 ResultInfo(int pkind, Type pt) { 435 this(pkind, pt, chk.basicHandler); 436 } 437 438 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) { 439 this.pkind = pkind; 440 this.pt = pt; 441 this.checkContext = checkContext; 442 } 443 444 protected Type check(final DiagnosticPosition pos, final Type found) { 445 return chk.checkType(pos, found, pt, checkContext); 446 } 447 448 protected ResultInfo dup(Type newPt) { 449 return new ResultInfo(pkind, newPt, checkContext); 450 } 451 452 protected ResultInfo dup(CheckContext newContext) { 453 return new ResultInfo(pkind, pt, newContext); 454 } 455 456 protected ResultInfo dup(Type newPt, CheckContext newContext) { 457 return new ResultInfo(pkind, newPt, newContext); 458 } 459 460 @Override 461 public String toString() { 462 if (pt != null) { 463 return pt.toString(); 464 } else { 465 return ""; 466 } 467 } 468 } 469 470 class RecoveryInfo extends ResultInfo { 471 472 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) { 473 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) { 474 @Override 475 public DeferredAttr.DeferredAttrContext deferredAttrContext() { 476 return deferredAttrContext; 477 } 478 @Override 479 public boolean compatible(Type found, Type req, Warner warn) { 480 return true; 481 } 482 @Override 483 public void report(DiagnosticPosition pos, JCDiagnostic details) { 484 chk.basicHandler.report(pos, details); 485 } 486 }); 487 } 488 } 489 490 final ResultInfo statInfo; 491 final ResultInfo varInfo; 492 final ResultInfo unknownAnyPolyInfo; 493 final ResultInfo unknownExprInfo; 494 final ResultInfo unknownTypeInfo; 495 final ResultInfo unknownTypeExprInfo; 496 final ResultInfo recoveryInfo; 497 498 Type pt() { 499 return resultInfo.pt; 500 } 501 502 int pkind() { 503 return resultInfo.pkind; 504 } 505 506/* ************************************************************************ 507 * Visitor methods 508 *************************************************************************/ 509 510 /** Visitor argument: the current environment. 511 */ 512 Env<AttrContext> env; 513 514 /** Visitor argument: the currently expected attribution result. 515 */ 516 ResultInfo resultInfo; 517 518 /** Visitor result: the computed type. 519 */ 520 Type result; 521 522 /** Visitor method: attribute a tree, catching any completion failure 523 * exceptions. Return the tree's type. 524 * 525 * @param tree The tree to be visited. 526 * @param env The environment visitor argument. 527 * @param resultInfo The result info visitor argument. 528 */ 529 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) { 530 Env<AttrContext> prevEnv = this.env; 531 ResultInfo prevResult = this.resultInfo; 532 try { 533 this.env = env; 534 this.resultInfo = resultInfo; 535 tree.accept(this); 536 if (tree == breakTree && 537 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) { 538 throw new BreakAttr(copyEnv(env)); 539 } 540 return result; 541 } catch (CompletionFailure ex) { 542 tree.type = syms.errType; 543 return chk.completionError(tree.pos(), ex); 544 } finally { 545 this.env = prevEnv; 546 this.resultInfo = prevResult; 547 } 548 } 549 550 Env<AttrContext> copyEnv(Env<AttrContext> env) { 551 Env<AttrContext> newEnv = 552 env.dup(env.tree, env.info.dup(copyScope(env.info.scope))); 553 if (newEnv.outer != null) { 554 newEnv.outer = copyEnv(newEnv.outer); 555 } 556 return newEnv; 557 } 558 559 WriteableScope copyScope(WriteableScope sc) { 560 WriteableScope newScope = WriteableScope.create(sc.owner); 561 List<Symbol> elemsList = List.nil(); 562 for (Symbol sym : sc.getSymbols()) { 563 elemsList = elemsList.prepend(sym); 564 } 565 for (Symbol s : elemsList) { 566 newScope.enter(s); 567 } 568 return newScope; 569 } 570 571 /** Derived visitor method: attribute an expression tree. 572 */ 573 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) { 574 return attribTree(tree, env, 575 new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType)); 576 } 577 578 /** Derived visitor method: attribute an expression tree with 579 * no constraints on the computed type. 580 */ 581 public Type attribExpr(JCTree tree, Env<AttrContext> env) { 582 return attribTree(tree, env, unknownExprInfo); 583 } 584 585 /** Derived visitor method: attribute a type tree. 586 */ 587 588 public Type attribType(JCTree tree, Env<AttrContext> env) { 589 Type result = attribType(tree, env, Type.noType); 590 return result; 591 } 592 593 /** Derived visitor method: attribute a type tree. 594 */ 595 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) { 596 Type result = attribTree(tree, env, new ResultInfo(TYP, pt)); 597 return result; 598 } 599 600 /** Derived visitor method: attribute a statement or definition tree. 601 */ 602 603 public Type attribStat(JCTree tree, Env<AttrContext> env) { 604 return attribTree(tree, env, statInfo); 605 } 606 607 /** Attribute a list of expressions, returning a list of types. 608 */ 609 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) { 610 ListBuffer<Type> ts = new ListBuffer<>(); 611 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) 612 ts.append(attribExpr(l.head, env, pt)); 613 return ts.toList(); 614 } 615 616 /** Attribute a list of statements, returning nothing. 617 */ 618 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) { 619 for (List<T> l = trees; l.nonEmpty(); l = l.tail) 620 attribStat(l.head, env); 621 } 622 623 /** Attribute the arguments in a method call, returning the method kind. 624 */ 625 int attribArgs(List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) { 626 int kind = VAL; 627 for (JCExpression arg : trees) { 628 Type argtype; 629 if (allowPoly && deferredAttr.isDeferred(env, arg)) { 630 argtype = deferredAttr.new DeferredType(arg, env); 631 kind |= POLY; 632 } else { 633 argtype = chk.checkNonVoid(arg, attribTree(arg, env, unknownAnyPolyInfo)); 634 } 635 argtypes.append(argtype); 636 } 637 return kind; 638 } 639 640 /** Attribute a type argument list, returning a list of types. 641 * Caller is responsible for calling checkRefTypes. 642 */ 643 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) { 644 ListBuffer<Type> argtypes = new ListBuffer<>(); 645 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) 646 argtypes.append(attribType(l.head, env)); 647 return argtypes.toList(); 648 } 649 650 /** Attribute a type argument list, returning a list of types. 651 * Check that all the types are references. 652 */ 653 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) { 654 List<Type> types = attribAnyTypes(trees, env); 655 return chk.checkRefTypes(trees, types); 656 } 657 658 /** 659 * Attribute type variables (of generic classes or methods). 660 * Compound types are attributed later in attribBounds. 661 * @param typarams the type variables to enter 662 * @param env the current environment 663 */ 664 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) { 665 for (JCTypeParameter tvar : typarams) { 666 dependencies.push(AttributionKind.TVAR, tvar); 667 TypeVar a = (TypeVar)tvar.type; 668 a.tsym.flags_field |= UNATTRIBUTED; 669 a.bound = Type.noType; 670 if (!tvar.bounds.isEmpty()) { 671 List<Type> bounds = 672 List.of(attribType(tvar.bounds.head, env)); 673 for (JCExpression bound : tvar.bounds.tail) 674 bounds = bounds.prepend(attribType(bound, env)); 675 types.setBounds(a, bounds.reverse()); 676 } else { 677 // if no bounds are given, assume a single bound of 678 // java.lang.Object. 679 types.setBounds(a, List.of(syms.objectType)); 680 } 681 a.tsym.flags_field &= ~UNATTRIBUTED; 682 dependencies.pop(); 683 } 684 for (JCTypeParameter tvar : typarams) { 685 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type); 686 } 687 } 688 689 /** 690 * Attribute the type references in a list of annotations. 691 */ 692 void attribAnnotationTypes(List<JCAnnotation> annotations, 693 Env<AttrContext> env) { 694 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) { 695 JCAnnotation a = al.head; 696 attribType(a.annotationType, env); 697 } 698 } 699 700 /** 701 * Attribute a "lazy constant value". 702 * @param env The env for the const value 703 * @param initializer The initializer for the const value 704 * @param type The expected type, or null 705 * @see VarSymbol#setLazyConstValue 706 */ 707 public Object attribLazyConstantValue(final Env<AttrContext> env, 708 JCVariableDecl variable, 709 Type type) { 710 711 DiagnosticPosition prevLintPos 712 = deferredLintHandler.setPos(variable.pos()); 713 714 try { 715 Type itype = attribExpr(variable.init, env, type); 716 if (itype.constValue() != null) { 717 return coerce(itype, type).constValue(); 718 } else { 719 return null; 720 } 721 } finally { 722 deferredLintHandler.setPos(prevLintPos); 723 } 724 } 725 726 /** Attribute type reference in an `extends' or `implements' clause. 727 * Supertypes of anonymous inner classes are usually already attributed. 728 * 729 * @param tree The tree making up the type reference. 730 * @param env The environment current at the reference. 731 * @param classExpected true if only a class is expected here. 732 * @param interfaceExpected true if only an interface is expected here. 733 */ 734 Type attribBase(JCTree tree, 735 Env<AttrContext> env, 736 boolean classExpected, 737 boolean interfaceExpected, 738 boolean checkExtensible) { 739 Type t = tree.type != null ? 740 tree.type : 741 attribType(tree, env); 742 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible); 743 } 744 Type checkBase(Type t, 745 JCTree tree, 746 Env<AttrContext> env, 747 boolean classExpected, 748 boolean interfaceExpected, 749 boolean checkExtensible) { 750 if (t.tsym.isAnonymous()) { 751 log.error(tree.pos(), "cant.inherit.from.anon"); 752 return types.createErrorType(t); 753 } 754 if (t.isErroneous()) 755 return t; 756 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) { 757 // check that type variable is already visible 758 if (t.getUpperBound() == null) { 759 log.error(tree.pos(), "illegal.forward.ref"); 760 return types.createErrorType(t); 761 } 762 } else { 763 t = chk.checkClassType(tree.pos(), t, checkExtensible); 764 } 765 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) { 766 log.error(tree.pos(), "intf.expected.here"); 767 // return errType is necessary since otherwise there might 768 // be undetected cycles which cause attribution to loop 769 return types.createErrorType(t); 770 } else if (checkExtensible && 771 classExpected && 772 (t.tsym.flags() & INTERFACE) != 0) { 773 log.error(tree.pos(), "no.intf.expected.here"); 774 return types.createErrorType(t); 775 } 776 if (checkExtensible && 777 ((t.tsym.flags() & FINAL) != 0)) { 778 log.error(tree.pos(), 779 "cant.inherit.from.final", t.tsym); 780 } 781 chk.checkNonCyclic(tree.pos(), t); 782 return t; 783 } 784 785 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) { 786 Assert.check((env.enclClass.sym.flags() & ENUM) != 0); 787 id.type = env.info.scope.owner.type; 788 id.sym = env.info.scope.owner; 789 return id.type; 790 } 791 792 public void visitClassDef(JCClassDecl tree) { 793 // Local and anonymous classes have not been entered yet, so we need to 794 // do it now. 795 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0) { 796 enter.classEnter(tree, env); 797 } else { 798 // If this class declaration is part of a class level annotation, 799 // as in @MyAnno(new Object() {}) class MyClass {}, enter it in 800 // order to simplify later steps and allow for sensible error 801 // messages. 802 if (env.tree.hasTag(NEWCLASS) && TreeInfo.isInAnnotation(env, tree)) 803 enter.classEnter(tree, env); 804 } 805 806 ClassSymbol c = tree.sym; 807 if (c == null) { 808 // exit in case something drastic went wrong during enter. 809 result = null; 810 } else { 811 // make sure class has been completed: 812 c.complete(); 813 814 // If this class appears as an anonymous class 815 // in a superclass constructor call where 816 // no explicit outer instance is given, 817 // disable implicit outer instance from being passed. 818 // (This would be an illegal access to "this before super"). 819 if (env.info.isSelfCall && 820 env.tree.hasTag(NEWCLASS) && 821 ((JCNewClass) env.tree).encl == null) 822 { 823 c.flags_field |= NOOUTERTHIS; 824 } 825 attribClass(tree.pos(), c); 826 827 result = tree.type = c.type; 828 } 829 } 830 831 public void visitMethodDef(JCMethodDecl tree) { 832 MethodSymbol m = tree.sym; 833 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0; 834 835 Lint lint = env.info.lint.augment(m); 836 Lint prevLint = chk.setLint(lint); 837 MethodSymbol prevMethod = chk.setMethod(m); 838 try { 839 deferredLintHandler.flush(tree.pos()); 840 chk.checkDeprecatedAnnotation(tree.pos(), m); 841 842 843 // Create a new environment with local scope 844 // for attributing the method. 845 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env); 846 localEnv.info.lint = lint; 847 848 attribStats(tree.typarams, localEnv); 849 850 // If we override any other methods, check that we do so properly. 851 // JLS ??? 852 if (m.isStatic()) { 853 chk.checkHideClashes(tree.pos(), env.enclClass.type, m); 854 } else { 855 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m); 856 } 857 chk.checkOverride(tree, m); 858 859 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) { 860 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location()); 861 } 862 863 // Enter all type parameters into the local method scope. 864 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail) 865 localEnv.info.scope.enterIfAbsent(l.head.type.tsym); 866 867 ClassSymbol owner = env.enclClass.sym; 868 if ((owner.flags() & ANNOTATION) != 0 && 869 tree.params.nonEmpty()) 870 log.error(tree.params.head.pos(), 871 "intf.annotation.members.cant.have.params"); 872 873 // Attribute all value parameters. 874 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { 875 attribStat(l.head, localEnv); 876 } 877 878 chk.checkVarargsMethodDecl(localEnv, tree); 879 880 // Check that type parameters are well-formed. 881 chk.validate(tree.typarams, localEnv); 882 883 // Check that result type is well-formed. 884 if (tree.restype != null && !tree.restype.type.hasTag(VOID)) 885 chk.validate(tree.restype, localEnv); 886 887 // Check that receiver type is well-formed. 888 if (tree.recvparam != null) { 889 // Use a new environment to check the receiver parameter. 890 // Otherwise I get "might not have been initialized" errors. 891 // Is there a better way? 892 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env); 893 attribType(tree.recvparam, newEnv); 894 chk.validate(tree.recvparam, newEnv); 895 } 896 897 // annotation method checks 898 if ((owner.flags() & ANNOTATION) != 0) { 899 // annotation method cannot have throws clause 900 if (tree.thrown.nonEmpty()) { 901 log.error(tree.thrown.head.pos(), 902 "throws.not.allowed.in.intf.annotation"); 903 } 904 // annotation method cannot declare type-parameters 905 if (tree.typarams.nonEmpty()) { 906 log.error(tree.typarams.head.pos(), 907 "intf.annotation.members.cant.have.type.params"); 908 } 909 // validate annotation method's return type (could be an annotation type) 910 chk.validateAnnotationType(tree.restype); 911 // ensure that annotation method does not clash with members of Object/Annotation 912 chk.validateAnnotationMethod(tree.pos(), m); 913 } 914 915 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail) 916 chk.checkType(l.head.pos(), l.head.type, syms.throwableType); 917 918 if (tree.body == null) { 919 // Empty bodies are only allowed for 920 // abstract, native, or interface methods, or for methods 921 // in a retrofit signature class. 922 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 && 923 !relax) 924 log.error(tree.pos(), "missing.meth.body.or.decl.abstract"); 925 if (tree.defaultValue != null) { 926 if ((owner.flags() & ANNOTATION) == 0) 927 log.error(tree.pos(), 928 "default.allowed.in.intf.annotation.member"); 929 } 930 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) { 931 if ((owner.flags() & INTERFACE) != 0) { 932 log.error(tree.body.pos(), "intf.meth.cant.have.body"); 933 } else { 934 log.error(tree.pos(), "abstract.meth.cant.have.body"); 935 } 936 } else if ((tree.mods.flags & NATIVE) != 0) { 937 log.error(tree.pos(), "native.meth.cant.have.body"); 938 } else { 939 // Add an implicit super() call unless an explicit call to 940 // super(...) or this(...) is given 941 // or we are compiling class java.lang.Object. 942 if (tree.name == names.init && owner.type != syms.objectType) { 943 JCBlock body = tree.body; 944 if (body.stats.isEmpty() || 945 !TreeInfo.isSelfCall(body.stats.head)) { 946 body.stats = body.stats. 947 prepend(memberEnter.SuperCall(make.at(body.pos), 948 List.<Type>nil(), 949 List.<JCVariableDecl>nil(), 950 false)); 951 } else if ((env.enclClass.sym.flags() & ENUM) != 0 && 952 (tree.mods.flags & GENERATEDCONSTR) == 0 && 953 TreeInfo.isSuperCall(body.stats.head)) { 954 // enum constructors are not allowed to call super 955 // directly, so make sure there aren't any super calls 956 // in enum constructors, except in the compiler 957 // generated one. 958 log.error(tree.body.stats.head.pos(), 959 "call.to.super.not.allowed.in.enum.ctor", 960 env.enclClass.sym); 961 } 962 } 963 964 // Attribute method body. 965 attribStat(tree.body, localEnv); 966 } 967 968 localEnv.info.scope.leave(); 969 result = tree.type = m.type; 970 } 971 finally { 972 chk.setLint(prevLint); 973 chk.setMethod(prevMethod); 974 } 975 } 976 977 public Annotate.PositionCreator getVarCreator(final JCVariableDecl tree) { 978 // Form the enclosing tree node, figure out what kind 979 // of definition we are looking at. 980 switch(env.tree.getTag()) { 981 case TRY: 982 // If it's a try, then we have a resource variable 983 return annotate.resourceVarCreator(tree.pos); 984 case CATCH: 985 // If it's a catch, then we have an exception parameter 986 return annotate.exceptionParamCreator(tree.pos); 987 case LAMBDA: { 988 // If it's a lambda, then we could have a local 989 // variable or a parameter. 990 final JCLambda lambda = (JCLambda) env.tree; 991 // We have to figure out what the index of the 992 // parameter is, and unfortunately, the visitor 993 // and tree APIs don't help us much here. If we 994 // don't find the declaration in the parameter 995 // list, then it must be a local variable. 996 // 997 // This could easily be replaced by an index 998 // parameter, which is -1 for non-indexed 999 // definitions. 1000 int index = -1; 1001 int i = 0; 1002 for (List<JCVariableDecl> l = lambda.params; 1003 l.nonEmpty(); l = l.tail, i++) { 1004 if (l.head == tree) { 1005 index = i; 1006 break; 1007 } 1008 } 1009 if (index == -1) { 1010 return annotate.localVarCreator(tree.pos); 1011 } else { 1012 return annotate.paramCreator(index); 1013 } 1014 } 1015 default: 1016 // The default case is to treat any declaration as a local 1017 // variable. 1018 return annotate.localVarCreator(tree.pos); 1019 } 1020 } 1021 1022 public void visitVarDef(final JCVariableDecl tree) { 1023 // Local variables have not been entered yet, so we need to do it now: 1024 if (env.info.scope.owner.kind == MTH) { 1025 if (tree.sym != null) { 1026 // parameters have already been entered 1027 env.info.scope.enter(tree.sym); 1028 } else { 1029 memberEnter.memberEnter(tree, env, getVarCreator(tree)); 1030 } 1031 } 1032 1033 VarSymbol v = tree.sym; 1034 Lint lint = env.info.lint.augment(v); 1035 Lint prevLint = chk.setLint(lint); 1036 1037 // Check that the variable's declared type is well-formed. 1038 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) && 1039 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT && 1040 (tree.sym.flags() & PARAMETER) != 0; 1041 chk.validate(tree.vartype, env, !isImplicitLambdaParameter); 1042 1043 try { 1044 v.getConstValue(); // ensure compile-time constant initializer is evaluated 1045 deferredLintHandler.flush(tree.pos()); 1046 chk.checkDeprecatedAnnotation(tree.pos(), v); 1047 1048 if (tree.init != null) { 1049 if ((v.flags_field & FINAL) == 0 || 1050 !memberEnter.needsLazyConstValue(tree.init)) { 1051 // Not a compile-time constant 1052 // Attribute initializer in a new environment 1053 // with the declared variable as owner. 1054 // Check that initializer conforms to variable's declared type. 1055 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env); 1056 initEnv.info.lint = lint; 1057 // In order to catch self-references, we set the variable's 1058 // declaration position to maximal possible value, effectively 1059 // marking the variable as undefined. 1060 initEnv.info.enclVar = v; 1061 attribExpr(tree.init, initEnv, v.type); 1062 } 1063 } 1064 result = tree.type = v.type; 1065 } 1066 finally { 1067 chk.setLint(prevLint); 1068 } 1069 } 1070 1071 public void visitSkip(JCSkip tree) { 1072 result = null; 1073 } 1074 1075 public void visitBlock(JCBlock tree) { 1076 if (env.info.scope.owner.kind == TYP) { 1077 // Block is a static or instance initializer; 1078 // let the owner of the environment be a freshly 1079 // created BLOCK-method. 1080 Symbol fakeOwner = 1081 new MethodSymbol(tree.flags | BLOCK | 1082 env.info.scope.owner.flags() & STRICTFP, names.empty, null, 1083 env.info.scope.owner); 1084 final Env<AttrContext> localEnv = 1085 env.dup(tree, env.info.dup(env.info.scope.dupUnshared(fakeOwner))); 1086 1087 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++; 1088 attribStats(tree.stats, localEnv); 1089 1090 { 1091 // Store init and clinit type annotations with the ClassSymbol 1092 // to allow output in Gen.normalizeDefs. 1093 ClassSymbol cs = (ClassSymbol)env.info.scope.owner; 1094 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes(); 1095 if ((tree.flags & STATIC) != 0) { 1096 cs.appendClassInitTypeAttributes(tas); 1097 } else { 1098 cs.appendInitTypeAttributes(tas); 1099 } 1100 } 1101 } else { 1102 // Create a new local environment with a local scope. 1103 Env<AttrContext> localEnv = 1104 env.dup(tree, env.info.dup(env.info.scope.dup())); 1105 try { 1106 attribStats(tree.stats, localEnv); 1107 } finally { 1108 localEnv.info.scope.leave(); 1109 } 1110 } 1111 result = null; 1112 } 1113 1114 public void visitDoLoop(JCDoWhileLoop tree) { 1115 attribStat(tree.body, env.dup(tree)); 1116 attribExpr(tree.cond, env, syms.booleanType); 1117 result = null; 1118 } 1119 1120 public void visitWhileLoop(JCWhileLoop tree) { 1121 attribExpr(tree.cond, env, syms.booleanType); 1122 attribStat(tree.body, env.dup(tree)); 1123 result = null; 1124 } 1125 1126 public void visitForLoop(JCForLoop tree) { 1127 Env<AttrContext> loopEnv = 1128 env.dup(env.tree, env.info.dup(env.info.scope.dup())); 1129 try { 1130 attribStats(tree.init, loopEnv); 1131 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType); 1132 loopEnv.tree = tree; // before, we were not in loop! 1133 attribStats(tree.step, loopEnv); 1134 attribStat(tree.body, loopEnv); 1135 result = null; 1136 } 1137 finally { 1138 loopEnv.info.scope.leave(); 1139 } 1140 } 1141 1142 public void visitForeachLoop(JCEnhancedForLoop tree) { 1143 Env<AttrContext> loopEnv = 1144 env.dup(env.tree, env.info.dup(env.info.scope.dup())); 1145 try { 1146 //the Formal Parameter of a for-each loop is not in the scope when 1147 //attributing the for-each expression; we mimick this by attributing 1148 //the for-each expression first (against original scope). 1149 Type exprType = types.cvarUpperBound(attribExpr(tree.expr, loopEnv)); 1150 attribStat(tree.var, loopEnv); 1151 chk.checkNonVoid(tree.pos(), exprType); 1152 Type elemtype = types.elemtype(exprType); // perhaps expr is an array? 1153 if (elemtype == null) { 1154 // or perhaps expr implements Iterable<T>? 1155 Type base = types.asSuper(exprType, syms.iterableType.tsym); 1156 if (base == null) { 1157 log.error(tree.expr.pos(), 1158 "foreach.not.applicable.to.type", 1159 exprType, 1160 diags.fragment("type.req.array.or.iterable")); 1161 elemtype = types.createErrorType(exprType); 1162 } else { 1163 List<Type> iterableParams = base.allparams(); 1164 elemtype = iterableParams.isEmpty() 1165 ? syms.objectType 1166 : types.wildUpperBound(iterableParams.head); 1167 } 1168 } 1169 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type); 1170 loopEnv.tree = tree; // before, we were not in loop! 1171 attribStat(tree.body, loopEnv); 1172 result = null; 1173 } 1174 finally { 1175 loopEnv.info.scope.leave(); 1176 } 1177 } 1178 1179 public void visitLabelled(JCLabeledStatement tree) { 1180 // Check that label is not used in an enclosing statement 1181 Env<AttrContext> env1 = env; 1182 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) { 1183 if (env1.tree.hasTag(LABELLED) && 1184 ((JCLabeledStatement) env1.tree).label == tree.label) { 1185 log.error(tree.pos(), "label.already.in.use", 1186 tree.label); 1187 break; 1188 } 1189 env1 = env1.next; 1190 } 1191 1192 attribStat(tree.body, env.dup(tree)); 1193 result = null; 1194 } 1195 1196 public void visitSwitch(JCSwitch tree) { 1197 Type seltype = attribExpr(tree.selector, env); 1198 1199 Env<AttrContext> switchEnv = 1200 env.dup(tree, env.info.dup(env.info.scope.dup())); 1201 1202 try { 1203 1204 boolean enumSwitch = (seltype.tsym.flags() & Flags.ENUM) != 0; 1205 boolean stringSwitch = false; 1206 if (types.isSameType(seltype, syms.stringType)) { 1207 if (allowStringsInSwitch) { 1208 stringSwitch = true; 1209 } else { 1210 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName); 1211 } 1212 } 1213 if (!enumSwitch && !stringSwitch) 1214 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType); 1215 1216 // Attribute all cases and 1217 // check that there are no duplicate case labels or default clauses. 1218 Set<Object> labels = new HashSet<>(); // The set of case labels. 1219 boolean hasDefault = false; // Is there a default label? 1220 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) { 1221 JCCase c = l.head; 1222 Env<AttrContext> caseEnv = 1223 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup())); 1224 try { 1225 if (c.pat != null) { 1226 if (enumSwitch) { 1227 Symbol sym = enumConstant(c.pat, seltype); 1228 if (sym == null) { 1229 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum"); 1230 } else if (!labels.add(sym)) { 1231 log.error(c.pos(), "duplicate.case.label"); 1232 } 1233 } else { 1234 Type pattype = attribExpr(c.pat, switchEnv, seltype); 1235 if (!pattype.hasTag(ERROR)) { 1236 if (pattype.constValue() == null) { 1237 log.error(c.pat.pos(), 1238 (stringSwitch ? "string.const.req" : "const.expr.req")); 1239 } else if (labels.contains(pattype.constValue())) { 1240 log.error(c.pos(), "duplicate.case.label"); 1241 } else { 1242 labels.add(pattype.constValue()); 1243 } 1244 } 1245 } 1246 } else if (hasDefault) { 1247 log.error(c.pos(), "duplicate.default.label"); 1248 } else { 1249 hasDefault = true; 1250 } 1251 attribStats(c.stats, caseEnv); 1252 } finally { 1253 caseEnv.info.scope.leave(); 1254 addVars(c.stats, switchEnv.info.scope); 1255 } 1256 } 1257 1258 result = null; 1259 } 1260 finally { 1261 switchEnv.info.scope.leave(); 1262 } 1263 } 1264 // where 1265 /** Add any variables defined in stats to the switch scope. */ 1266 private static void addVars(List<JCStatement> stats, WriteableScope switchScope) { 1267 for (;stats.nonEmpty(); stats = stats.tail) { 1268 JCTree stat = stats.head; 1269 if (stat.hasTag(VARDEF)) 1270 switchScope.enter(((JCVariableDecl) stat).sym); 1271 } 1272 } 1273 // where 1274 /** Return the selected enumeration constant symbol, or null. */ 1275 private Symbol enumConstant(JCTree tree, Type enumType) { 1276 if (!tree.hasTag(IDENT)) { 1277 log.error(tree.pos(), "enum.label.must.be.unqualified.enum"); 1278 return syms.errSymbol; 1279 } 1280 JCIdent ident = (JCIdent)tree; 1281 Name name = ident.name; 1282 for (Symbol sym : enumType.tsym.members().getSymbolsByName(name)) { 1283 if (sym.kind == VAR) { 1284 Symbol s = ident.sym = sym; 1285 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated 1286 ident.type = s.type; 1287 return ((s.flags_field & Flags.ENUM) == 0) 1288 ? null : s; 1289 } 1290 } 1291 return null; 1292 } 1293 1294 public void visitSynchronized(JCSynchronized tree) { 1295 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env)); 1296 attribStat(tree.body, env); 1297 result = null; 1298 } 1299 1300 public void visitTry(JCTry tree) { 1301 // Create a new local environment with a local 1302 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup())); 1303 try { 1304 boolean isTryWithResource = tree.resources.nonEmpty(); 1305 // Create a nested environment for attributing the try block if needed 1306 Env<AttrContext> tryEnv = isTryWithResource ? 1307 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) : 1308 localEnv; 1309 try { 1310 // Attribute resource declarations 1311 for (JCTree resource : tree.resources) { 1312 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) { 1313 @Override 1314 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1315 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details)); 1316 } 1317 }; 1318 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext); 1319 if (resource.hasTag(VARDEF)) { 1320 attribStat(resource, tryEnv); 1321 twrResult.check(resource, resource.type); 1322 1323 //check that resource type cannot throw InterruptedException 1324 checkAutoCloseable(resource.pos(), localEnv, resource.type); 1325 1326 VarSymbol var = ((JCVariableDecl) resource).sym; 1327 var.setData(ElementKind.RESOURCE_VARIABLE); 1328 } else { 1329 attribTree(resource, tryEnv, twrResult); 1330 } 1331 } 1332 // Attribute body 1333 attribStat(tree.body, tryEnv); 1334 } finally { 1335 if (isTryWithResource) 1336 tryEnv.info.scope.leave(); 1337 } 1338 1339 // Attribute catch clauses 1340 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { 1341 JCCatch c = l.head; 1342 Env<AttrContext> catchEnv = 1343 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup())); 1344 try { 1345 Type ctype = attribStat(c.param, catchEnv); 1346 if (TreeInfo.isMultiCatch(c)) { 1347 //multi-catch parameter is implicitly marked as final 1348 c.param.sym.flags_field |= FINAL | UNION; 1349 } 1350 if (c.param.sym.kind == Kinds.VAR) { 1351 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER); 1352 } 1353 chk.checkType(c.param.vartype.pos(), 1354 chk.checkClassType(c.param.vartype.pos(), ctype), 1355 syms.throwableType); 1356 attribStat(c.body, catchEnv); 1357 } finally { 1358 catchEnv.info.scope.leave(); 1359 } 1360 } 1361 1362 // Attribute finalizer 1363 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv); 1364 result = null; 1365 } 1366 finally { 1367 localEnv.info.scope.leave(); 1368 } 1369 } 1370 1371 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) { 1372 if (!resource.isErroneous() && 1373 types.asSuper(resource, syms.autoCloseableType.tsym) != null && 1374 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself 1375 Symbol close = syms.noSymbol; 1376 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log); 1377 try { 1378 close = rs.resolveQualifiedMethod(pos, 1379 env, 1380 resource, 1381 names.close, 1382 List.<Type>nil(), 1383 List.<Type>nil()); 1384 } 1385 finally { 1386 log.popDiagnosticHandler(discardHandler); 1387 } 1388 if (close.kind == MTH && 1389 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) && 1390 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) && 1391 env.info.lint.isEnabled(LintCategory.TRY)) { 1392 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource); 1393 } 1394 } 1395 } 1396 1397 public void visitConditional(JCConditional tree) { 1398 Type condtype = attribExpr(tree.cond, env, syms.booleanType); 1399 1400 tree.polyKind = (!allowPoly || 1401 pt().hasTag(NONE) && pt() != Type.recoveryType || 1402 isBooleanOrNumeric(env, tree)) ? 1403 PolyKind.STANDALONE : PolyKind.POLY; 1404 1405 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) { 1406 //cannot get here (i.e. it means we are returning from void method - which is already an error) 1407 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void")); 1408 result = tree.type = types.createErrorType(resultInfo.pt); 1409 return; 1410 } 1411 1412 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ? 1413 unknownExprInfo : 1414 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) { 1415 //this will use enclosing check context to check compatibility of 1416 //subexpression against target type; if we are in a method check context, 1417 //depending on whether boxing is allowed, we could have incompatibilities 1418 @Override 1419 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1420 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details)); 1421 } 1422 }); 1423 1424 Type truetype = attribTree(tree.truepart, env, condInfo); 1425 Type falsetype = attribTree(tree.falsepart, env, condInfo); 1426 1427 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt(); 1428 if (condtype.constValue() != null && 1429 truetype.constValue() != null && 1430 falsetype.constValue() != null && 1431 !owntype.hasTag(NONE)) { 1432 //constant folding 1433 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype); 1434 } 1435 result = check(tree, owntype, VAL, resultInfo); 1436 } 1437 //where 1438 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) { 1439 switch (tree.getTag()) { 1440 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) || 1441 ((JCLiteral)tree).typetag == BOOLEAN || 1442 ((JCLiteral)tree).typetag == BOT; 1443 case LAMBDA: case REFERENCE: return false; 1444 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr); 1445 case CONDEXPR: 1446 JCConditional condTree = (JCConditional)tree; 1447 return isBooleanOrNumeric(env, condTree.truepart) && 1448 isBooleanOrNumeric(env, condTree.falsepart); 1449 case APPLY: 1450 JCMethodInvocation speculativeMethodTree = 1451 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo, 1452 annotate.noCreator); 1453 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType(); 1454 return types.unboxedTypeOrType(owntype).isPrimitive(); 1455 case NEWCLASS: 1456 JCExpression className = 1457 removeClassParams.translate(((JCNewClass)tree).clazz); 1458 JCExpression speculativeNewClassTree = 1459 (JCExpression)deferredAttr.attribSpeculative(className, 1460 env, 1461 unknownTypeInfo, 1462 annotate.newObjCreator(tree.pos)); 1463 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive(); 1464 default: 1465 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo, annotate.noCreator).type; 1466 speculativeType = types.unboxedTypeOrType(speculativeType); 1467 return speculativeType.isPrimitive(); 1468 } 1469 } 1470 //where 1471 TreeTranslator removeClassParams = new TreeTranslator() { 1472 @Override 1473 public void visitTypeApply(JCTypeApply tree) { 1474 result = translate(tree.clazz); 1475 } 1476 }; 1477 1478 /** Compute the type of a conditional expression, after 1479 * checking that it exists. See JLS 15.25. Does not take into 1480 * account the special case where condition and both arms 1481 * are constants. 1482 * 1483 * @param pos The source position to be used for error 1484 * diagnostics. 1485 * @param thentype The type of the expression's then-part. 1486 * @param elsetype The type of the expression's else-part. 1487 */ 1488 private Type condType(DiagnosticPosition pos, 1489 Type thentype, Type elsetype) { 1490 // If same type, that is the result 1491 if (types.isSameType(thentype, elsetype)) 1492 return thentype.baseType(); 1493 1494 Type thenUnboxed = (thentype.isPrimitive()) 1495 ? thentype : types.unboxedType(thentype); 1496 Type elseUnboxed = (elsetype.isPrimitive()) 1497 ? elsetype : types.unboxedType(elsetype); 1498 1499 // Otherwise, if both arms can be converted to a numeric 1500 // type, return the least numeric type that fits both arms 1501 // (i.e. return larger of the two, or return int if one 1502 // arm is short, the other is char). 1503 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) { 1504 // If one arm has an integer subrange type (i.e., byte, 1505 // short, or char), and the other is an integer constant 1506 // that fits into the subrange, return the subrange type. 1507 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) && 1508 elseUnboxed.hasTag(INT) && 1509 types.isAssignable(elseUnboxed, thenUnboxed)) { 1510 return thenUnboxed.baseType(); 1511 } 1512 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) && 1513 thenUnboxed.hasTag(INT) && 1514 types.isAssignable(thenUnboxed, elseUnboxed)) { 1515 return elseUnboxed.baseType(); 1516 } 1517 1518 for (TypeTag tag : primitiveTags) { 1519 Type candidate = syms.typeOfTag[tag.ordinal()]; 1520 if (types.isSubtype(thenUnboxed, candidate) && 1521 types.isSubtype(elseUnboxed, candidate)) { 1522 return candidate; 1523 } 1524 } 1525 } 1526 1527 // Those were all the cases that could result in a primitive 1528 if (thentype.isPrimitive()) 1529 thentype = types.boxedClass(thentype).type; 1530 if (elsetype.isPrimitive()) 1531 elsetype = types.boxedClass(elsetype).type; 1532 1533 if (types.isSubtype(thentype, elsetype)) 1534 return elsetype.baseType(); 1535 if (types.isSubtype(elsetype, thentype)) 1536 return thentype.baseType(); 1537 1538 if (thentype.hasTag(VOID) || elsetype.hasTag(VOID)) { 1539 log.error(pos, "neither.conditional.subtype", 1540 thentype, elsetype); 1541 return thentype.baseType(); 1542 } 1543 1544 // both are known to be reference types. The result is 1545 // lub(thentype,elsetype). This cannot fail, as it will 1546 // always be possible to infer "Object" if nothing better. 1547 return types.lub(thentype.baseType(), elsetype.baseType()); 1548 } 1549 1550 final static TypeTag[] primitiveTags = new TypeTag[]{ 1551 BYTE, 1552 CHAR, 1553 SHORT, 1554 INT, 1555 LONG, 1556 FLOAT, 1557 DOUBLE, 1558 BOOLEAN, 1559 }; 1560 1561 public void visitIf(JCIf tree) { 1562 attribExpr(tree.cond, env, syms.booleanType); 1563 attribStat(tree.thenpart, env); 1564 if (tree.elsepart != null) 1565 attribStat(tree.elsepart, env); 1566 chk.checkEmptyIf(tree); 1567 result = null; 1568 } 1569 1570 public void visitExec(JCExpressionStatement tree) { 1571 //a fresh environment is required for 292 inference to work properly --- 1572 //see Infer.instantiatePolymorphicSignatureInstance() 1573 Env<AttrContext> localEnv = env.dup(tree); 1574 attribExpr(tree.expr, localEnv); 1575 result = null; 1576 } 1577 1578 public void visitBreak(JCBreak tree) { 1579 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); 1580 result = null; 1581 } 1582 1583 public void visitContinue(JCContinue tree) { 1584 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); 1585 result = null; 1586 } 1587 //where 1588 /** Return the target of a break or continue statement, if it exists, 1589 * report an error if not. 1590 * Note: The target of a labelled break or continue is the 1591 * (non-labelled) statement tree referred to by the label, 1592 * not the tree representing the labelled statement itself. 1593 * 1594 * @param pos The position to be used for error diagnostics 1595 * @param tag The tag of the jump statement. This is either 1596 * Tree.BREAK or Tree.CONTINUE. 1597 * @param label The label of the jump statement, or null if no 1598 * label is given. 1599 * @param env The environment current at the jump statement. 1600 */ 1601 private JCTree findJumpTarget(DiagnosticPosition pos, 1602 JCTree.Tag tag, 1603 Name label, 1604 Env<AttrContext> env) { 1605 // Search environments outwards from the point of jump. 1606 Env<AttrContext> env1 = env; 1607 LOOP: 1608 while (env1 != null) { 1609 switch (env1.tree.getTag()) { 1610 case LABELLED: 1611 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree; 1612 if (label == labelled.label) { 1613 // If jump is a continue, check that target is a loop. 1614 if (tag == CONTINUE) { 1615 if (!labelled.body.hasTag(DOLOOP) && 1616 !labelled.body.hasTag(WHILELOOP) && 1617 !labelled.body.hasTag(FORLOOP) && 1618 !labelled.body.hasTag(FOREACHLOOP)) 1619 log.error(pos, "not.loop.label", label); 1620 // Found labelled statement target, now go inwards 1621 // to next non-labelled tree. 1622 return TreeInfo.referencedStatement(labelled); 1623 } else { 1624 return labelled; 1625 } 1626 } 1627 break; 1628 case DOLOOP: 1629 case WHILELOOP: 1630 case FORLOOP: 1631 case FOREACHLOOP: 1632 if (label == null) return env1.tree; 1633 break; 1634 case SWITCH: 1635 if (label == null && tag == BREAK) return env1.tree; 1636 break; 1637 case LAMBDA: 1638 case METHODDEF: 1639 case CLASSDEF: 1640 break LOOP; 1641 default: 1642 } 1643 env1 = env1.next; 1644 } 1645 if (label != null) 1646 log.error(pos, "undef.label", label); 1647 else if (tag == CONTINUE) 1648 log.error(pos, "cont.outside.loop"); 1649 else 1650 log.error(pos, "break.outside.switch.loop"); 1651 return null; 1652 } 1653 1654 public void visitReturn(JCReturn tree) { 1655 // Check that there is an enclosing method which is 1656 // nested within than the enclosing class. 1657 if (env.info.returnResult == null) { 1658 log.error(tree.pos(), "ret.outside.meth"); 1659 } else { 1660 // Attribute return expression, if it exists, and check that 1661 // it conforms to result type of enclosing method. 1662 if (tree.expr != null) { 1663 if (env.info.returnResult.pt.hasTag(VOID)) { 1664 env.info.returnResult.checkContext.report(tree.expr.pos(), 1665 diags.fragment("unexpected.ret.val")); 1666 } 1667 attribTree(tree.expr, env, env.info.returnResult); 1668 } else if (!env.info.returnResult.pt.hasTag(VOID) && 1669 !env.info.returnResult.pt.hasTag(NONE)) { 1670 env.info.returnResult.checkContext.report(tree.pos(), 1671 diags.fragment("missing.ret.val")); 1672 } 1673 } 1674 result = null; 1675 } 1676 1677 public void visitThrow(JCThrow tree) { 1678 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType); 1679 if (allowPoly) { 1680 chk.checkType(tree, owntype, syms.throwableType); 1681 } 1682 result = null; 1683 } 1684 1685 public void visitAssert(JCAssert tree) { 1686 attribExpr(tree.cond, env, syms.booleanType); 1687 if (tree.detail != null) { 1688 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env)); 1689 } 1690 result = null; 1691 } 1692 1693 /** Visitor method for method invocations. 1694 * NOTE: The method part of an application will have in its type field 1695 * the return type of the method, not the method's type itself! 1696 */ 1697 public void visitApply(JCMethodInvocation tree) { 1698 // The local environment of a method application is 1699 // a new environment nested in the current one. 1700 Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); 1701 1702 // The types of the actual method arguments. 1703 List<Type> argtypes; 1704 1705 // The types of the actual method type arguments. 1706 List<Type> typeargtypes = null; 1707 1708 Name methName = TreeInfo.name(tree.meth); 1709 1710 boolean isConstructorCall = 1711 methName == names._this || methName == names._super; 1712 1713 ListBuffer<Type> argtypesBuf = new ListBuffer<>(); 1714 if (isConstructorCall) { 1715 // We are seeing a ...this(...) or ...super(...) call. 1716 // Check that this is the first statement in a constructor. 1717 if (checkFirstConstructorStat(tree, env)) { 1718 1719 // Record the fact 1720 // that this is a constructor call (using isSelfCall). 1721 localEnv.info.isSelfCall = true; 1722 1723 // Attribute arguments, yielding list of argument types. 1724 attribArgs(tree.args, localEnv, argtypesBuf); 1725 argtypes = argtypesBuf.toList(); 1726 1727 // Attribute and annotate the type arguments 1728 ListBuffer<Type> typeargtypesbuf = new ListBuffer<>(); 1729 int i = 0; 1730 1731 for (List<JCExpression> l = tree.typeargs; 1732 l.nonEmpty(); l = l.tail, i++) { 1733 final JCExpression arg = l.head; 1734 try { 1735 annotate.enterStart(); 1736 typeargtypesbuf.append(attribType(arg, localEnv)); 1737 annotate.annotateTypeLater(arg, localEnv, 1738 localEnv.info.scope.owner, 1739 tree.pos(), 1740 annotate.constructorInvokeTypeArgCreator(i, tree.pos)); 1741 } finally { 1742 annotate.enterDone(); 1743 } 1744 } 1745 1746 typeargtypes = 1747 chk.checkRefTypes(tree.typeargs, typeargtypesbuf.toList()); 1748 1749 // Variable `site' points to the class in which the called 1750 // constructor is defined. 1751 Type site = env.enclClass.sym.type; 1752 if (methName == names._super) { 1753 if (site == syms.objectType) { 1754 log.error(tree.meth.pos(), "no.superclass", site); 1755 site = types.createErrorType(syms.objectType); 1756 } else { 1757 site = types.supertype(site); 1758 } 1759 } 1760 1761 if (site.hasTag(CLASS)) { 1762 Type encl = site.getEnclosingType(); 1763 while (encl != null && encl.hasTag(TYPEVAR)) 1764 encl = encl.getUpperBound(); 1765 if (encl.hasTag(CLASS)) { 1766 // we are calling a nested class 1767 1768 if (tree.meth.hasTag(SELECT)) { 1769 JCTree qualifier = ((JCFieldAccess) tree.meth).selected; 1770 1771 // We are seeing a prefixed call, of the form 1772 // <expr>.super(...). 1773 // Check that the prefix expression conforms 1774 // to the outer instance type of the class. 1775 chk.checkRefType(qualifier.pos(), 1776 attribExpr(qualifier, localEnv, 1777 encl)); 1778 } else if (methName == names._super) { 1779 // qualifier omitted; check for existence 1780 // of an appropriate implicit qualifier. 1781 rs.resolveImplicitThis(tree.meth.pos(), 1782 localEnv, site, true); 1783 } 1784 } else if (tree.meth.hasTag(SELECT)) { 1785 log.error(tree.meth.pos(), "illegal.qual.not.icls", 1786 site.tsym); 1787 } 1788 1789 // if we're calling a java.lang.Enum constructor, 1790 // prefix the implicit String and int parameters 1791 if (site.tsym == syms.enumSym) 1792 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType); 1793 1794 // Resolve the called constructor under the assumption 1795 // that we are referring to a superclass instance of the 1796 // current instance (JLS ???). 1797 boolean selectSuperPrev = localEnv.info.selectSuper; 1798 localEnv.info.selectSuper = true; 1799 localEnv.info.pendingResolutionPhase = null; 1800 Symbol sym = rs.resolveConstructor( 1801 tree.meth.pos(), localEnv, site, argtypes, typeargtypes); 1802 localEnv.info.selectSuper = selectSuperPrev; 1803 1804 // Set method symbol to resolved constructor... 1805 TreeInfo.setSymbol(tree.meth, sym); 1806 1807 // ...and check that it is legal in the current context. 1808 // (this will also set the tree's type) 1809 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes); 1810 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt)); 1811 } 1812 // Otherwise, `site' is an error type and we do nothing 1813 } 1814 result = tree.type = syms.voidType; 1815 } else { 1816 // Otherwise, we are seeing a regular method call. 1817 // Attribute the arguments, yielding list of argument types, ... 1818 int kind = attribArgs(tree.args, localEnv, argtypesBuf); 1819 argtypes = argtypesBuf.toList(); 1820 1821 // Attribute and annotate the type arguments 1822 ListBuffer<Type> typeargtypesbuf = new ListBuffer<>(); 1823 int i = 0; 1824 1825 for (List<JCExpression> l = tree.typeargs; 1826 l.nonEmpty(); l = l.tail, i++) { 1827 final JCExpression arg = l.head; 1828 try { 1829 annotate.enterStart(); 1830 typeargtypesbuf.append(attribType(arg, localEnv)); 1831 annotate.annotateTypeLater(arg, localEnv, 1832 localEnv.info.scope.owner, 1833 tree.pos(), 1834 annotate.methodInvokeTypeArgCreator(i, tree.pos)); 1835 } finally { 1836 annotate.enterDone(); 1837 } 1838 } 1839 1840 typeargtypes = typeargtypesbuf.toList(); 1841 1842 // ... and attribute the method using as a prototype a methodtype 1843 // whose formal argument types is exactly the list of actual 1844 // arguments (this will also set the method symbol). 1845 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes); 1846 localEnv.info.pendingResolutionPhase = null; 1847 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext)); 1848 1849 // Compute the result type. 1850 Type restype = mtype.getReturnType(); 1851 if (restype.hasTag(WILDCARD)) 1852 throw new AssertionError(mtype); 1853 1854 Type qualifier = (tree.meth.hasTag(SELECT)) 1855 ? ((JCFieldAccess) tree.meth).selected.type 1856 : env.enclClass.sym.type; 1857 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype); 1858 1859 chk.checkRefTypes(tree.typeargs, typeargtypes); 1860 1861 // Check that value of resulting type is admissible in the 1862 // current context. Also, capture the return type 1863 result = check(tree, capture(restype), VAL, resultInfo); 1864 } 1865 1866 chk.validate(tree.typeargs, localEnv); 1867 } 1868 //where 1869 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) { 1870 if (methodName == names.clone && types.isArray(qualifierType)) { 1871 // as a special case, array.clone() has a result that is 1872 // the same as static type of the array being cloned 1873 return qualifierType; 1874 } else if (methodName == names.getClass && argtypes.isEmpty()) { 1875 // as a special case, x.getClass() has type Class<? extends |X|> 1876 return new ClassType(restype.getEnclosingType(), 1877 List.<Type>of(new WildcardType(types.erasure(qualifierType), 1878 BoundKind.EXTENDS, 1879 syms.boundClass, 1880 Type.noAnnotations)), 1881 restype.tsym, 1882 restype.getAnnotationMirrors()); 1883 } else { 1884 return restype; 1885 } 1886 } 1887 1888 /** Check that given application node appears as first statement 1889 * in a constructor call. 1890 * @param tree The application node 1891 * @param env The environment current at the application. 1892 */ 1893 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) { 1894 JCMethodDecl enclMethod = env.enclMethod; 1895 if (enclMethod != null && enclMethod.name == names.init) { 1896 JCBlock body = enclMethod.body; 1897 if (body.stats.head.hasTag(EXEC) && 1898 ((JCExpressionStatement) body.stats.head).expr == tree) 1899 return true; 1900 } 1901 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor", 1902 TreeInfo.name(tree.meth)); 1903 return false; 1904 } 1905 1906 /** Obtain a method type with given argument types. 1907 */ 1908 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) { 1909 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass); 1910 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt); 1911 } 1912 1913 public void visitNewClass(final JCNewClass tree) { 1914 Type owntype = types.createErrorType(tree.type); 1915 1916 // The local environment of a class creation is 1917 // a new environment nested in the current one. 1918 Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); 1919 1920 // The anonymous inner class definition of the new expression, 1921 // if one is defined by it. 1922 JCClassDecl cdef = tree.def; 1923 1924 // If enclosing class is given, attribute it, and 1925 // complete class name to be fully qualified 1926 JCExpression clazz = tree.clazz; // Class field following new 1927 JCExpression clazzid; // Identifier in class field 1928 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid 1929 annoclazzid = null; 1930 1931 if (clazz.hasTag(TYPEAPPLY)) { 1932 clazzid = ((JCTypeApply) clazz).clazz; 1933 if (clazzid.hasTag(ANNOTATED_TYPE)) { 1934 annoclazzid = (JCAnnotatedType) clazzid; 1935 clazzid = annoclazzid.underlyingType; 1936 } 1937 } else if (clazz.hasTag(ANNOTATED_TYPE)) { 1938 annoclazzid = (JCAnnotatedType) clazz; 1939 clazzid = annoclazzid.underlyingType; 1940 } else { 1941 clazzid = clazz; 1942 } 1943 1944 JCExpression clazzid1 = clazzid; // The same in fully qualified form 1945 1946 if (tree.encl != null) { 1947 // We are seeing a qualified new, of the form 1948 // <expr>.new C <...> (...) ... 1949 // In this case, we let clazz stand for the name of the 1950 // allocated class C prefixed with the type of the qualifier 1951 // expression, so that we can 1952 // resolve it with standard techniques later. I.e., if 1953 // <expr> has type T, then <expr>.new C <...> (...) 1954 // yields a clazz T.C. 1955 Type encltype = chk.checkRefType(tree.encl.pos(), 1956 attribExpr(tree.encl, env)); 1957 // TODO 308: in <expr>.new C, do we also want to add the type annotations 1958 // from expr to the combined type, or not? Yes, do this. 1959 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype), 1960 ((JCIdent) clazzid).name); 1961 1962 EndPosTable endPosTable = this.env.toplevel.endPositions; 1963 endPosTable.storeEnd(clazzid1, tree.getEndPosition(endPosTable)); 1964 if (annoclazzid != null) { 1965 JCAnnotatedType annoType = annoclazzid; 1966 List<JCAnnotation> annos = annoclazzid.annotations; 1967 1968 if (clazz.hasTag(TYPEAPPLY)) { 1969 1970 clazzid1 = make.at(tree.pos). 1971 TypeApply(clazzid1, 1972 ((JCTypeApply) clazz).arguments); 1973 } 1974 1975 clazzid1 = make.at(tree.pos). 1976 AnnotatedType(annos, clazzid1); 1977 } else if (clazz.hasTag(TYPEAPPLY)) { 1978 clazzid1 = make.at(tree.pos). 1979 TypeApply(clazzid1, 1980 ((JCTypeApply) clazz).arguments); 1981 } 1982 1983 clazz = clazzid1; 1984 } 1985 1986 Type clazztype; 1987 1988 try { 1989 annotate.enterStart(); 1990 // Attribute clazz expression and store 1991 // symbol + type back into the attributed tree. 1992 clazztype = TreeInfo.isEnumInit(env.tree) ? 1993 attribIdentAsEnumType(env, (JCIdent)clazz) : 1994 attribType(clazz, env); 1995 1996 if (cdef != null) { 1997 // If we are looking at an anonymous class creation, then 1998 // we are not allowed to have declaration annotations on 1999 // the base type. 2000 annotate.annotateStrictTypeLater(clazz, cdef.mods.annotations, localEnv, 2001 env.info.scope.owner, tree.pos(), 2002 annotate.newObjCreator(tree.pos)); 2003 } else { 2004 // Otherwise, we are. 2005 annotate.annotateTypeLater(clazz, localEnv, env.info.scope.owner, 2006 tree.pos(), annotate.newObjCreator(tree.pos)); 2007 } 2008 } finally { 2009 annotate.enterDone(); 2010 } 2011 2012 clazztype = chk.checkDiamond(tree, clazztype); 2013 chk.validate(clazz, localEnv); 2014 if (tree.encl != null) { 2015 // We have to work in this case to store 2016 // symbol + type back into the attributed tree. 2017 tree.clazz.type = clazztype; 2018 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1)); 2019 clazzid.type = ((JCIdent) clazzid).sym.type; 2020 if (annoclazzid != null) { 2021 annoclazzid.type = clazzid.type; 2022 } 2023 if (!clazztype.isErroneous()) { 2024 if (cdef != null && clazztype.tsym.isInterface()) { 2025 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new"); 2026 } else if (clazztype.tsym.isStatic()) { 2027 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym); 2028 } 2029 } 2030 } else if (!clazztype.tsym.isInterface() && 2031 clazztype.getEnclosingType().hasTag(CLASS)) { 2032 // Check for the existence of an apropos outer instance 2033 rs.resolveImplicitThis(tree.pos(), env, clazztype); 2034 } 2035 2036 // Attribute constructor arguments. 2037 ListBuffer<Type> argtypesBuf = new ListBuffer<>(); 2038 int pkind = attribArgs(tree.args, localEnv, argtypesBuf); 2039 List<Type> argtypes = argtypesBuf.toList(); 2040 List<Type> typeargtypes; 2041 2042 // Attribute and annotate the type arguments 2043 ListBuffer<Type> typeargtypesbuf = new ListBuffer<>(); 2044 int i = 0; 2045 2046 for (List<JCExpression> l = tree.typeargs; 2047 l.nonEmpty(); l = l.tail, i++) { 2048 final JCExpression arg = l.head; 2049 try { 2050 annotate.enterStart(); 2051 typeargtypesbuf.append(attribType(arg, localEnv)); 2052 annotate.annotateTypeLater(arg, localEnv, 2053 localEnv.info.scope.owner, 2054 tree.pos(), 2055 annotate.constructorInvokeTypeArgCreator(i, tree.pos)); 2056 } finally { 2057 annotate.enterDone(); 2058 } 2059 } 2060 2061 typeargtypes = 2062 chk.checkRefTypes(tree.typeargs, typeargtypesbuf.toList()); 2063 2064 // If we have made no mistakes in the class type... 2065 if (clazztype.hasTag(CLASS)) { 2066 // Enums may not be instantiated except implicitly 2067 if ((clazztype.tsym.flags_field & Flags.ENUM) != 0 && 2068 (!env.tree.hasTag(VARDEF) || 2069 (((JCVariableDecl) env.tree).mods.flags & Flags.ENUM) == 0 || 2070 ((JCVariableDecl) env.tree).init != tree)) 2071 log.error(tree.pos(), "enum.cant.be.instantiated"); 2072 // Check that class is not abstract 2073 if (cdef == null && 2074 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 2075 log.error(tree.pos(), "abstract.cant.be.instantiated", 2076 clazztype.tsym); 2077 } else if (cdef != null && clazztype.tsym.isInterface()) { 2078 // Check that no constructor arguments are given to 2079 // anonymous classes implementing an interface 2080 if (!argtypes.isEmpty()) 2081 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args"); 2082 2083 if (!typeargtypes.isEmpty()) 2084 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs"); 2085 2086 // Error recovery: pretend no arguments were supplied. 2087 argtypes = List.nil(); 2088 typeargtypes = List.nil(); 2089 } else if (TreeInfo.isDiamond(tree)) { 2090 ClassType site = new ClassType(clazztype.getEnclosingType(), 2091 clazztype.tsym.type.getTypeArguments(), 2092 clazztype.tsym, 2093 clazztype.getAnnotationMirrors()); 2094 2095 Env<AttrContext> diamondEnv = localEnv.dup(tree); 2096 diamondEnv.info.selectSuper = cdef != null; 2097 diamondEnv.info.pendingResolutionPhase = null; 2098 2099 //if the type of the instance creation expression is a class type 2100 //apply method resolution inference (JLS 15.12.2.7). The return type 2101 //of the resolved constructor will be a partially instantiated type 2102 Symbol constructor = rs.resolveDiamond(tree.pos(), 2103 diamondEnv, 2104 site, 2105 argtypes, 2106 typeargtypes); 2107 tree.constructor = constructor.baseSymbol(); 2108 2109 final TypeSymbol csym = clazztype.tsym; 2110 ResultInfo diamondResult = new ResultInfo(pkind, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) { 2111 @Override 2112 public void report(DiagnosticPosition _unused, JCDiagnostic details) { 2113 enclosingContext.report(tree.clazz, 2114 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details)); 2115 } 2116 }); 2117 Type constructorType = tree.constructorType = types.createErrorType(clazztype); 2118 constructorType = checkId(tree, site, 2119 constructor, 2120 diamondEnv, 2121 diamondResult); 2122 2123 tree.clazz.type = types.createErrorType(clazztype); 2124 if (!constructorType.isErroneous()) { 2125 tree.clazz.type = clazztype = constructorType.getReturnType(); 2126 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType); 2127 } 2128 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true); 2129 } 2130 2131 // Resolve the called constructor under the assumption 2132 // that we are referring to a superclass instance of the 2133 // current instance (JLS ???). 2134 else { 2135 //the following code alters some of the fields in the current 2136 //AttrContext - hence, the current context must be dup'ed in 2137 //order to avoid downstream failures 2138 Env<AttrContext> rsEnv = localEnv.dup(tree); 2139 rsEnv.info.selectSuper = cdef != null; 2140 rsEnv.info.pendingResolutionPhase = null; 2141 tree.constructor = rs.resolveConstructor( 2142 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes); 2143 if (cdef == null) { //do not check twice! 2144 tree.constructorType = checkId(tree, 2145 clazztype, 2146 tree.constructor, 2147 rsEnv, 2148 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes))); 2149 if (rsEnv.info.lastResolveVarargs()) 2150 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null); 2151 } 2152 if (cdef == null && 2153 !clazztype.isErroneous() && 2154 clazztype.getTypeArguments().nonEmpty() && 2155 findDiamonds) { 2156 findDiamond(localEnv, tree, clazztype); 2157 } 2158 } 2159 2160 if (cdef != null) { 2161 // We are seeing an anonymous class instance creation. 2162 // In this case, the class instance creation 2163 // expression 2164 // 2165 // E.new <typeargs1>C<typargs2>(args) { ... } 2166 // 2167 // is represented internally as 2168 // 2169 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) . 2170 // 2171 // This expression is then *transformed* as follows: 2172 // 2173 // (1) add an extends or implements clause 2174 // (2) add a constructor. 2175 // 2176 // For instance, if C is a class, and ET is the type of E, 2177 // the expression 2178 // 2179 // E.new <typeargs1>C<typargs2>(args) { ... } 2180 // 2181 // is translated to (where X is a fresh name and typarams is the 2182 // parameter list of the super constructor): 2183 // 2184 // new <typeargs1>X(<*nullchk*>E, args) where 2185 // X extends C<typargs2> { 2186 // <typarams> X(ET e, args) { 2187 // e.<typeargs1>super(args) 2188 // } 2189 // ... 2190 // } 2191 2192 if (clazztype.tsym.isInterface()) { 2193 cdef.implementing = List.of(clazz); 2194 } else { 2195 cdef.extending = clazz; 2196 } 2197 2198 if (resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK && 2199 isSerializable(clazztype)) { 2200 localEnv.info.isSerializable = true; 2201 } 2202 2203 attribStat(cdef, localEnv); 2204 2205 checkLambdaCandidate(tree, cdef.sym, clazztype); 2206 2207 // If an outer instance is given, 2208 // prefix it to the constructor arguments 2209 // and delete it from the new expression 2210 if (tree.encl != null && !clazztype.tsym.isInterface()) { 2211 tree.args = tree.args.prepend(makeNullCheck(tree.encl)); 2212 argtypes = argtypes.prepend(tree.encl.type); 2213 tree.encl = null; 2214 } 2215 2216 // Reassign clazztype and recompute constructor. 2217 clazztype = cdef.sym.type; 2218 Symbol sym = tree.constructor = rs.resolveConstructor( 2219 tree.pos(), localEnv, clazztype, argtypes, typeargtypes); 2220 Assert.check(sym.kind < AMBIGUOUS); 2221 tree.constructor = sym; 2222 tree.constructorType = checkId(tree, 2223 clazztype, 2224 tree.constructor, 2225 localEnv, 2226 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes))); 2227 } 2228 2229 if (tree.constructor != null && tree.constructor.kind == MTH) 2230 owntype = clazztype; 2231 } 2232 result = check(tree, owntype, VAL, resultInfo); 2233 chk.validate(tree.typeargs, localEnv); 2234 } 2235 //where 2236 void findDiamond(Env<AttrContext> env, JCNewClass tree, Type clazztype) { 2237 JCTypeApply ta = (JCTypeApply)tree.clazz; 2238 List<JCExpression> prevTypeargs = ta.arguments; 2239 try { 2240 //create a 'fake' diamond AST node by removing type-argument trees 2241 ta.arguments = List.nil(); 2242 ResultInfo findDiamondResult = new ResultInfo(VAL, 2243 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt()); 2244 Type inferred = deferredAttr.attribSpeculative(tree, env, 2245 findDiamondResult, 2246 annotate.newObjCreator(tree.pos)).type; 2247 Type polyPt = allowPoly ? 2248 syms.objectType : 2249 clazztype; 2250 if (!inferred.isErroneous() && 2251 (allowPoly && pt() == Infer.anyPoly ? 2252 types.isSameType(inferred, clazztype) : 2253 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings))) { 2254 String key = types.isSameType(clazztype, inferred) ? 2255 "diamond.redundant.args" : 2256 "diamond.redundant.args.1"; 2257 log.warning(tree.clazz.pos(), key, clazztype, inferred); 2258 } 2259 } finally { 2260 ta.arguments = prevTypeargs; 2261 } 2262 } 2263 2264 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) { 2265 if (allowLambda && 2266 identifyLambdaCandidate && 2267 clazztype.hasTag(CLASS) && 2268 !pt().hasTag(NONE) && 2269 types.isFunctionalInterface(clazztype.tsym)) { 2270 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym); 2271 int count = 0; 2272 boolean found = false; 2273 for (Symbol sym : csym.members().getSymbols()) { 2274 if ((sym.flags() & SYNTHETIC) != 0 || 2275 sym.isConstructor()) continue; 2276 count++; 2277 if (sym.kind != MTH || 2278 !sym.name.equals(descriptor.name)) continue; 2279 Type mtype = types.memberType(clazztype, sym); 2280 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) { 2281 found = true; 2282 } 2283 } 2284 if (found && count == 1) { 2285 log.note(tree.def, "potential.lambda.found"); 2286 } 2287 } 2288 } 2289 2290 /** Make an attributed null check tree. 2291 */ 2292 public JCExpression makeNullCheck(JCExpression arg) { 2293 // optimization: X.this is never null; skip null check 2294 Name name = TreeInfo.name(arg); 2295 if (name == names._this || name == names._super) return arg; 2296 2297 JCTree.Tag optag = NULLCHK; 2298 JCUnary tree = make.at(arg.pos).Unary(optag, arg); 2299 tree.operator = syms.nullcheck; 2300 tree.type = arg.type; 2301 return tree; 2302 } 2303 2304 public void visitNewArray(JCNewArray tree) { 2305 Type owntype = types.createErrorType(tree.type); 2306 Env<AttrContext> localEnv = env.dup(tree); 2307 Type elemtype; 2308 2309 for(List<JCAnnotation> dim : tree.dimAnnotations) { 2310 this.attribAnnotationTypes(dim, localEnv); 2311 } 2312 2313 if (tree.elemtype != null) { 2314 try { 2315 annotate.enterStart(); 2316 elemtype = attribType(tree.elemtype, localEnv); 2317 annotate.annotateTypeLater(tree, env, env.info.scope.owner, tree.pos(), 2318 annotate.newObjCreator(tree.pos)); 2319 } finally { 2320 annotate.enterDone(); 2321 } 2322 chk.validate(tree.elemtype, localEnv); 2323 owntype = elemtype; 2324 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) { 2325 attribExpr(l.head, localEnv, syms.intType); 2326 owntype = new ArrayType(owntype, syms.arrayClass, 2327 Type.noAnnotations); 2328 } 2329 } else { 2330 // we are seeing an untyped aggregate { ... } 2331 // this is allowed only if the prototype is an array 2332 if (pt().hasTag(ARRAY)) { 2333 elemtype = types.elemtype(pt()); 2334 } else { 2335 if (!pt().hasTag(ERROR)) { 2336 log.error(tree.pos(), "illegal.initializer.for.type", 2337 pt()); 2338 } 2339 elemtype = types.createErrorType(pt()); 2340 } 2341 } 2342 2343 if (tree.elems != null) { 2344 attribExprs(tree.elems, localEnv, elemtype); 2345 owntype = new ArrayType(elemtype, syms.arrayClass, 2346 Type.noAnnotations); 2347 } 2348 if (!types.isReifiable(elemtype)) 2349 log.error(tree.pos(), "generic.array.creation"); 2350 result = check(tree, owntype, VAL, resultInfo); 2351 } 2352 2353 /* 2354 * A lambda expression can only be attributed when a target-type is available. 2355 * In addition, if the target-type is that of a functional interface whose 2356 * descriptor contains inference variables in argument position the lambda expression 2357 * is 'stuck' (see DeferredAttr). 2358 */ 2359 @Override 2360 public void visitLambda(final JCLambda that) { 2361 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) { 2362 if (pt().hasTag(NONE)) { 2363 //lambda only allowed in assignment or method invocation/cast context 2364 log.error(that.pos(), "unexpected.lambda"); 2365 } 2366 result = that.type = types.createErrorType(pt()); 2367 return; 2368 } 2369 //create an environment for attribution of the lambda expression 2370 final Env<AttrContext> localEnv = lambdaEnv(that, env); 2371 boolean needsRecovery = 2372 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK; 2373 try { 2374 Type currentTarget = pt(); 2375 if (needsRecovery && isSerializable(currentTarget)) { 2376 localEnv.info.isSerializable = true; 2377 } 2378 List<Type> explicitParamTypes = null; 2379 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) { 2380 //attribute lambda parameters 2381 attribStats(that.params, localEnv); 2382 explicitParamTypes = TreeInfo.types(that.params); 2383 } 2384 2385 Type lambdaType; 2386 if (pt() != Type.recoveryType) { 2387 /* We need to adjust the target. If the target is an 2388 * intersection type, for example: SAM & I1 & I2 ... 2389 * the target will be updated to SAM 2390 */ 2391 currentTarget = targetChecker.visit(currentTarget, that); 2392 if (explicitParamTypes != null) { 2393 currentTarget = infer.instantiateFunctionalInterface(that, 2394 currentTarget, explicitParamTypes, resultInfo.checkContext); 2395 } 2396 currentTarget = types.removeWildcards(currentTarget); 2397 lambdaType = types.findDescriptorType(currentTarget); 2398 } else { 2399 currentTarget = Type.recoveryType; 2400 lambdaType = fallbackDescriptorType(that); 2401 } 2402 2403 setFunctionalInfo(localEnv, that, pt(), lambdaType, currentTarget, resultInfo.checkContext); 2404 2405 if (lambdaType.hasTag(FORALL)) { 2406 //lambda expression target desc cannot be a generic method 2407 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target", 2408 lambdaType, kindName(currentTarget.tsym), currentTarget.tsym)); 2409 result = that.type = types.createErrorType(pt()); 2410 return; 2411 } 2412 2413 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) { 2414 //add param type info in the AST 2415 List<Type> actuals = lambdaType.getParameterTypes(); 2416 List<JCVariableDecl> params = that.params; 2417 2418 boolean arityMismatch = false; 2419 2420 while (params.nonEmpty()) { 2421 if (actuals.isEmpty()) { 2422 //not enough actuals to perform lambda parameter inference 2423 arityMismatch = true; 2424 } 2425 //reset previously set info 2426 Type argType = arityMismatch ? 2427 syms.errType : 2428 actuals.head; 2429 params.head.vartype = make.at(params.head).Type(argType); 2430 params.head.sym = null; 2431 actuals = actuals.isEmpty() ? 2432 actuals : 2433 actuals.tail; 2434 params = params.tail; 2435 } 2436 2437 //attribute lambda parameters 2438 attribStats(that.params, localEnv); 2439 2440 if (arityMismatch) { 2441 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda")); 2442 result = that.type = types.createErrorType(currentTarget); 2443 return; 2444 } 2445 } 2446 2447 //from this point on, no recovery is needed; if we are in assignment context 2448 //we will be able to attribute the whole lambda body, regardless of errors; 2449 //if we are in a 'check' method context, and the lambda is not compatible 2450 //with the target-type, it will be recovered anyway in Attr.checkId 2451 needsRecovery = false; 2452 2453 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ? 2454 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) : 2455 new FunctionalReturnContext(resultInfo.checkContext); 2456 2457 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ? 2458 recoveryInfo : 2459 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext); 2460 localEnv.info.returnResult = bodyResultInfo; 2461 2462 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) { 2463 attribTree(that.getBody(), localEnv, bodyResultInfo); 2464 } else { 2465 JCBlock body = (JCBlock)that.body; 2466 attribStats(body.stats, localEnv); 2467 } 2468 2469 result = check(that, currentTarget, VAL, resultInfo); 2470 2471 boolean isSpeculativeRound = 2472 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE; 2473 2474 preFlow(that); 2475 flow.analyzeLambda(env, that, make, isSpeculativeRound); 2476 2477 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext); 2478 2479 if (!isSpeculativeRound) { 2480 //add thrown types as bounds to the thrown types free variables if needed: 2481 if (resultInfo.checkContext.inferenceContext().free(lambdaType.getThrownTypes())) { 2482 List<Type> inferredThrownTypes = flow.analyzeLambdaThrownTypes(env, that, make); 2483 List<Type> thrownTypes = resultInfo.checkContext.inferenceContext().asUndetVars(lambdaType.getThrownTypes()); 2484 2485 chk.unhandled(inferredThrownTypes, thrownTypes); 2486 } 2487 2488 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, currentTarget); 2489 } 2490 result = check(that, currentTarget, VAL, resultInfo); 2491 } catch (Types.FunctionDescriptorLookupError ex) { 2492 JCDiagnostic cause = ex.getDiagnostic(); 2493 resultInfo.checkContext.report(that, cause); 2494 result = that.type = types.createErrorType(pt()); 2495 return; 2496 } finally { 2497 localEnv.info.scope.leave(); 2498 if (needsRecovery) { 2499 attribTree(that, env, recoveryInfo); 2500 } 2501 } 2502 } 2503 //where 2504 void preFlow(JCLambda tree) { 2505 new PostAttrAnalyzer() { 2506 @Override 2507 public void scan(JCTree tree) { 2508 if (tree == null || 2509 (tree.type != null && 2510 tree.type == Type.stuckType)) { 2511 //don't touch stuck expressions! 2512 return; 2513 } 2514 super.scan(tree); 2515 } 2516 }.scan(tree); 2517 } 2518 2519 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() { 2520 2521 @Override 2522 public Type visitClassType(ClassType t, DiagnosticPosition pos) { 2523 return t.isCompound() ? 2524 visitIntersectionClassType((IntersectionClassType)t, pos) : t; 2525 } 2526 2527 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) { 2528 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict)); 2529 Type target = null; 2530 for (Type bound : ict.getExplicitComponents()) { 2531 TypeSymbol boundSym = bound.tsym; 2532 if (types.isFunctionalInterface(boundSym) && 2533 types.findDescriptorSymbol(boundSym) == desc) { 2534 target = bound; 2535 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) { 2536 //bound must be an interface 2537 reportIntersectionError(pos, "not.an.intf.component", boundSym); 2538 } 2539 } 2540 return target != null ? 2541 target : 2542 ict.getExplicitComponents().head; //error recovery 2543 } 2544 2545 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) { 2546 ListBuffer<Type> targs = new ListBuffer<>(); 2547 ListBuffer<Type> supertypes = new ListBuffer<>(); 2548 for (Type i : ict.interfaces_field) { 2549 if (i.isParameterized()) { 2550 targs.appendList(i.tsym.type.allparams()); 2551 } 2552 supertypes.append(i.tsym.type); 2553 } 2554 IntersectionClassType notionalIntf = 2555 (IntersectionClassType)types.makeCompoundType(supertypes.toList()); 2556 notionalIntf.allparams_field = targs.toList(); 2557 notionalIntf.tsym.flags_field |= INTERFACE; 2558 return notionalIntf.tsym; 2559 } 2560 2561 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) { 2562 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr", 2563 diags.fragment(key, args))); 2564 } 2565 }; 2566 2567 private Type fallbackDescriptorType(JCExpression tree) { 2568 switch (tree.getTag()) { 2569 case LAMBDA: 2570 JCLambda lambda = (JCLambda)tree; 2571 List<Type> argtypes = List.nil(); 2572 for (JCVariableDecl param : lambda.params) { 2573 argtypes = param.vartype != null ? 2574 argtypes.append(param.vartype.type) : 2575 argtypes.append(syms.errType); 2576 } 2577 return new MethodType(argtypes, Type.recoveryType, 2578 List.of(syms.throwableType), syms.methodClass); 2579 case REFERENCE: 2580 return new MethodType(List.<Type>nil(), Type.recoveryType, 2581 List.of(syms.throwableType), syms.methodClass); 2582 default: 2583 Assert.error("Cannot get here!"); 2584 } 2585 return null; 2586 } 2587 2588 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, 2589 final InferenceContext inferenceContext, final Type... ts) { 2590 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts)); 2591 } 2592 2593 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, 2594 final InferenceContext inferenceContext, final List<Type> ts) { 2595 if (inferenceContext.free(ts)) { 2596 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() { 2597 @Override 2598 public void typesInferred(InferenceContext inferenceContext) { 2599 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts)); 2600 } 2601 }); 2602 } else { 2603 for (Type t : ts) { 2604 rs.checkAccessibleType(env, t); 2605 } 2606 } 2607 } 2608 2609 /** 2610 * Lambda/method reference have a special check context that ensures 2611 * that i.e. a lambda return type is compatible with the expected 2612 * type according to both the inherited context and the assignment 2613 * context. 2614 */ 2615 class FunctionalReturnContext extends Check.NestedCheckContext { 2616 2617 FunctionalReturnContext(CheckContext enclosingContext) { 2618 super(enclosingContext); 2619 } 2620 2621 @Override 2622 public boolean compatible(Type found, Type req, Warner warn) { 2623 //return type must be compatible in both current context and assignment context 2624 return chk.basicHandler.compatible(found, inferenceContext().asUndetVar(req), warn); 2625 } 2626 2627 @Override 2628 public void report(DiagnosticPosition pos, JCDiagnostic details) { 2629 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details)); 2630 } 2631 } 2632 2633 class ExpressionLambdaReturnContext extends FunctionalReturnContext { 2634 2635 JCExpression expr; 2636 2637 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) { 2638 super(enclosingContext); 2639 this.expr = expr; 2640 } 2641 2642 @Override 2643 public boolean compatible(Type found, Type req, Warner warn) { 2644 //a void return is compatible with an expression statement lambda 2645 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) || 2646 super.compatible(found, req, warn); 2647 } 2648 } 2649 2650 /** 2651 * Lambda compatibility. Check that given return types, thrown types, parameter types 2652 * are compatible with the expected functional interface descriptor. This means that: 2653 * (i) parameter types must be identical to those of the target descriptor; (ii) return 2654 * types must be compatible with the return type of the expected descriptor. 2655 */ 2656 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext) { 2657 Type returnType = checkContext.inferenceContext().asUndetVar(descriptor.getReturnType()); 2658 2659 //return values have already been checked - but if lambda has no return 2660 //values, we must ensure that void/value compatibility is correct; 2661 //this amounts at checking that, if a lambda body can complete normally, 2662 //the descriptor's return type must be void 2663 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally && 2664 !returnType.hasTag(VOID) && returnType != Type.recoveryType) { 2665 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda", 2666 diags.fragment("missing.ret.val", returnType))); 2667 } 2668 2669 List<Type> argTypes = checkContext.inferenceContext().asUndetVars(descriptor.getParameterTypes()); 2670 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) { 2671 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda")); 2672 } 2673 } 2674 2675 /* Map to hold 'fake' clinit methods. If a lambda is used to initialize a 2676 * static field and that lambda has type annotations, these annotations will 2677 * also be stored at these fake clinit methods. 2678 * 2679 * LambdaToMethod also use fake clinit methods so they can be reused. 2680 * Also as LTM is a phase subsequent to attribution, the methods from 2681 * clinits can be safely removed by LTM to save memory. 2682 */ 2683 private Map<ClassSymbol, MethodSymbol> clinits = new HashMap<>(); 2684 2685 public MethodSymbol removeClinit(ClassSymbol sym) { 2686 return clinits.remove(sym); 2687 } 2688 2689 /* This method returns an environment to be used to attribute a lambda 2690 * expression. 2691 * 2692 * The owner of this environment is a method symbol. If the current owner 2693 * is not a method, for example if the lambda is used to initialize 2694 * a field, then if the field is: 2695 * 2696 * - an instance field, we use the first constructor. 2697 * - a static field, we create a fake clinit method. 2698 */ 2699 public Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) { 2700 Env<AttrContext> lambdaEnv; 2701 Symbol owner = env.info.scope.owner; 2702 if (owner.kind == VAR && owner.owner.kind == TYP) { 2703 //field initializer 2704 ClassSymbol enclClass = owner.enclClass(); 2705 Symbol newScopeOwner = env.info.scope.owner; 2706 /* if the field isn't static, then we can get the first constructor 2707 * and use it as the owner of the environment. This is what 2708 * LTM code is doing to look for type annotations so we are fine. 2709 */ 2710 if ((owner.flags() & STATIC) == 0) { 2711 for (Symbol s : enclClass.members_field.getSymbolsByName(names.init)) { 2712 newScopeOwner = s; 2713 break; 2714 } 2715 } else { 2716 /* if the field is static then we need to create a fake clinit 2717 * method, this method can later be reused by LTM. 2718 */ 2719 MethodSymbol clinit = clinits.get(enclClass); 2720 if (clinit == null) { 2721 Type clinitType = new MethodType(List.<Type>nil(), 2722 syms.voidType, List.<Type>nil(), syms.methodClass); 2723 clinit = new MethodSymbol(STATIC | SYNTHETIC | PRIVATE, 2724 names.clinit, clinitType, enclClass); 2725 clinit.params = List.<VarSymbol>nil(); 2726 clinits.put(enclClass, clinit); 2727 } 2728 newScopeOwner = clinit; 2729 } 2730 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared(newScopeOwner))); 2731 } else { 2732 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup())); 2733 } 2734 return lambdaEnv; 2735 } 2736 2737 @Override 2738 public void visitReference(final JCMemberReference that) { 2739 final boolean isConstructor = that.getName() == names.init; 2740 2741 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) { 2742 if (pt().hasTag(NONE)) { 2743 //method reference only allowed in assignment or method invocation/cast context 2744 log.error(that.pos(), "unexpected.mref"); 2745 } 2746 result = that.type = types.createErrorType(pt()); 2747 return; 2748 } 2749 final Env<AttrContext> localEnv = env.dup(that); 2750 try { 2751 Type exprType; 2752 try { 2753 annotate.enterStart(); 2754 //attribute member reference qualifier - if this is a constructor 2755 //reference, the expected kind must be a type 2756 exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that)); 2757 final Annotate.PositionCreator creator = 2758 isConstructor ? annotate.constructorRefCreator(that.pos) : 2759 annotate.methodRefCreator(that.pos); 2760 annotate.annotateTypeLater(that.expr, localEnv, env.info.scope.owner, 2761 that.pos(), creator); 2762 } finally { 2763 annotate.enterDone(); 2764 } 2765 2766 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) { 2767 exprType = chk.checkConstructorRefType(that.expr, exprType); 2768 if (!exprType.isErroneous() && 2769 exprType.isRaw() && 2770 that.typeargs != null) { 2771 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2772 diags.fragment("mref.infer.and.explicit.params")); 2773 exprType = types.createErrorType(exprType); 2774 } 2775 } 2776 2777 if (exprType.isErroneous()) { 2778 //if the qualifier expression contains problems, 2779 //give up attribution of method reference 2780 result = that.type = exprType; 2781 return; 2782 } 2783 2784 if (TreeInfo.isStaticSelector(that.expr, names)) { 2785 //if the qualifier is a type, validate it; raw warning check is 2786 //omitted as we don't know at this stage as to whether this is a 2787 //raw selector (because of inference) 2788 chk.validate(that.expr, env, false); 2789 } 2790 2791 //attrib type-arguments 2792 List<Type> typeargtypes = List.nil(); 2793 if (that.typeargs != null) { 2794 try { 2795 annotate.enterStart(); 2796 typeargtypes = attribTypes(that.typeargs, localEnv); 2797 2798 // Annotate type arguments 2799 int i = 0; 2800 for (List<JCExpression> l = that.typeargs; 2801 l.nonEmpty(); l = l.tail, i++) { 2802 final Annotate.PositionCreator typeArgCreator = 2803 isConstructor ? annotate.constructorRefTypeArgCreator(i, that.pos) : 2804 annotate.methodRefTypeArgCreator(i, that.pos); 2805 final JCExpression arg = l.head; 2806 annotate.annotateTypeLater(arg, env, env.info.scope.owner, 2807 that.pos(), typeArgCreator); 2808 } 2809 } finally { 2810 annotate.enterDone(); 2811 } 2812 } 2813 2814 Type desc; 2815 Type currentTarget = pt(); 2816 boolean isTargetSerializable = 2817 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK && 2818 isSerializable(currentTarget); 2819 if (currentTarget != Type.recoveryType) { 2820 currentTarget = types.removeWildcards(targetChecker.visit(currentTarget, that)); 2821 desc = types.findDescriptorType(currentTarget); 2822 } else { 2823 currentTarget = Type.recoveryType; 2824 desc = fallbackDescriptorType(that); 2825 } 2826 2827 setFunctionalInfo(localEnv, that, pt(), desc, currentTarget, resultInfo.checkContext); 2828 List<Type> argtypes = desc.getParameterTypes(); 2829 Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck; 2830 2831 if (resultInfo.checkContext.inferenceContext().free(argtypes)) { 2832 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext()); 2833 } 2834 2835 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null; 2836 List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save(); 2837 try { 2838 refResult = rs.resolveMemberReference(localEnv, that, that.expr.type, 2839 that.name, argtypes, typeargtypes, referenceCheck, 2840 resultInfo.checkContext.inferenceContext(), 2841 resultInfo.checkContext.deferredAttrContext().mode); 2842 } finally { 2843 resultInfo.checkContext.inferenceContext().rollback(saved_undet); 2844 } 2845 2846 Symbol refSym = refResult.fst; 2847 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd; 2848 2849 if (refSym.kind != MTH) { 2850 boolean targetError; 2851 switch (refSym.kind) { 2852 case ABSENT_MTH: 2853 targetError = false; 2854 break; 2855 case WRONG_MTH: 2856 case WRONG_MTHS: 2857 case AMBIGUOUS: 2858 case HIDDEN: 2859 case STATICERR: 2860 case MISSING_ENCL: 2861 case WRONG_STATICNESS: 2862 targetError = true; 2863 break; 2864 default: 2865 Assert.error("unexpected result kind " + refSym.kind); 2866 targetError = false; 2867 } 2868 2869 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym.baseSymbol()).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, 2870 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes); 2871 2872 JCDiagnostic.DiagnosticType diagKind = targetError ? 2873 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR; 2874 2875 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that, 2876 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag); 2877 2878 if (targetError && currentTarget == Type.recoveryType) { 2879 //a target error doesn't make sense during recovery stage 2880 //as we don't know what actual parameter types are 2881 result = that.type = currentTarget; 2882 return; 2883 } else { 2884 if (targetError) { 2885 resultInfo.checkContext.report(that, diag); 2886 } else { 2887 log.report(diag); 2888 } 2889 result = that.type = types.createErrorType(currentTarget); 2890 return; 2891 } 2892 } 2893 2894 that.sym = refSym.baseSymbol(); 2895 that.kind = lookupHelper.referenceKind(that.sym); 2896 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass()); 2897 2898 if (desc.getReturnType() == Type.recoveryType) { 2899 // stop here 2900 result = that.type = currentTarget; 2901 return; 2902 } 2903 2904 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) { 2905 2906 if (that.getMode() == ReferenceMode.INVOKE && 2907 TreeInfo.isStaticSelector(that.expr, names) && 2908 that.kind.isUnbound() && 2909 !desc.getParameterTypes().head.isParameterized()) { 2910 chk.checkRaw(that.expr, localEnv); 2911 } 2912 2913 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) && 2914 exprType.getTypeArguments().nonEmpty()) { 2915 //static ref with class type-args 2916 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2917 diags.fragment("static.mref.with.targs")); 2918 result = that.type = types.createErrorType(currentTarget); 2919 return; 2920 } 2921 2922 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) && 2923 !that.kind.isUnbound()) { 2924 //no static bound mrefs 2925 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2926 diags.fragment("static.bound.mref")); 2927 result = that.type = types.createErrorType(currentTarget); 2928 return; 2929 } 2930 2931 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) { 2932 // Check that super-qualified symbols are not abstract (JLS) 2933 rs.checkNonAbstract(that.pos(), that.sym); 2934 } 2935 2936 if (isTargetSerializable) { 2937 chk.checkElemAccessFromSerializableLambda(that); 2938 } 2939 } 2940 2941 ResultInfo checkInfo = 2942 resultInfo.dup(newMethodTemplate( 2943 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(), 2944 that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes), 2945 new FunctionalReturnContext(resultInfo.checkContext)); 2946 2947 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo); 2948 2949 if (that.kind.isUnbound() && 2950 resultInfo.checkContext.inferenceContext().free(argtypes.head)) { 2951 //re-generate inference constraints for unbound receiver 2952 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asUndetVar(argtypes.head), exprType)) { 2953 //cannot happen as this has already been checked - we just need 2954 //to regenerate the inference constraints, as that has been lost 2955 //as a result of the call to inferenceContext.save() 2956 Assert.error("Can't get here"); 2957 } 2958 } 2959 2960 if (!refType.isErroneous()) { 2961 refType = types.createMethodTypeWithReturn(refType, 2962 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType())); 2963 } 2964 2965 //go ahead with standard method reference compatibility check - note that param check 2966 //is a no-op (as this has been taken care during method applicability) 2967 boolean isSpeculativeRound = 2968 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE; 2969 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound); 2970 if (!isSpeculativeRound) { 2971 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, currentTarget); 2972 } 2973 result = check(that, currentTarget, VAL, resultInfo); 2974 } catch (Types.FunctionDescriptorLookupError ex) { 2975 JCDiagnostic cause = ex.getDiagnostic(); 2976 resultInfo.checkContext.report(that, cause); 2977 result = that.type = types.createErrorType(pt()); 2978 return; 2979 } 2980 } 2981 //where 2982 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) { 2983 //if this is a constructor reference, the expected kind must be a type 2984 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType); 2985 } 2986 2987 2988 @SuppressWarnings("fallthrough") 2989 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) { 2990 Type returnType = checkContext.inferenceContext().asUndetVar(descriptor.getReturnType()); 2991 2992 Type resType; 2993 switch (tree.getMode()) { 2994 case NEW: 2995 if (!tree.expr.type.isRaw()) { 2996 resType = tree.expr.type; 2997 break; 2998 } 2999 default: 3000 resType = refType.getReturnType(); 3001 } 3002 3003 Type incompatibleReturnType = resType; 3004 3005 if (returnType.hasTag(VOID)) { 3006 incompatibleReturnType = null; 3007 } 3008 3009 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) { 3010 if (resType.isErroneous() || 3011 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) { 3012 incompatibleReturnType = null; 3013 } 3014 } 3015 3016 if (incompatibleReturnType != null) { 3017 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref", 3018 diags.fragment("inconvertible.types", resType, descriptor.getReturnType()))); 3019 } 3020 3021 if (!speculativeAttr) { 3022 List<Type> thrownTypes = checkContext.inferenceContext().asUndetVars(descriptor.getThrownTypes()); 3023 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) { 3024 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes()); 3025 } 3026 } 3027 } 3028 3029 /** 3030 * Set functional type info on the underlying AST. Note: as the target descriptor 3031 * might contain inference variables, we might need to register an hook in the 3032 * current inference context. 3033 */ 3034 private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr, 3035 final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) { 3036 if (checkContext.inferenceContext().free(descriptorType)) { 3037 checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() { 3038 public void typesInferred(InferenceContext inferenceContext) { 3039 setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType), 3040 inferenceContext.asInstType(primaryTarget), checkContext); 3041 } 3042 }); 3043 } else { 3044 ListBuffer<Type> targets = new ListBuffer<>(); 3045 if (pt.hasTag(CLASS)) { 3046 if (pt.isCompound()) { 3047 targets.append(types.removeWildcards(primaryTarget)); //this goes first 3048 for (Type t : ((IntersectionClassType)pt()).interfaces_field) { 3049 if (t != primaryTarget) { 3050 targets.append(types.removeWildcards(t)); 3051 } 3052 } 3053 } else { 3054 targets.append(types.removeWildcards(primaryTarget)); 3055 } 3056 } 3057 fExpr.targets = targets.toList(); 3058 if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK && 3059 pt != Type.recoveryType) { 3060 //check that functional interface class is well-formed 3061 try { 3062 /* Types.makeFunctionalInterfaceClass() may throw an exception 3063 * when it's executed post-inference. See the listener code 3064 * above. 3065 */ 3066 ClassSymbol csym = types.makeFunctionalInterfaceClass(env, 3067 names.empty, List.of(fExpr.targets.head), ABSTRACT); 3068 if (csym != null) { 3069 chk.checkImplementations(env.tree, csym, csym); 3070 } 3071 } catch (Types.FunctionDescriptorLookupError ex) { 3072 JCDiagnostic cause = ex.getDiagnostic(); 3073 resultInfo.checkContext.report(env.tree, cause); 3074 } 3075 } 3076 } 3077 } 3078 3079 public void visitParens(JCParens tree) { 3080 Type owntype = attribTree(tree.expr, env, resultInfo); 3081 result = check(tree, owntype, pkind(), resultInfo); 3082 Symbol sym = TreeInfo.symbol(tree); 3083 if (sym != null && (sym.kind&(TYP|PCK)) != 0) 3084 log.error(tree.pos(), "illegal.start.of.type"); 3085 } 3086 3087 public void visitAssign(JCAssign tree) { 3088 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo); 3089 Type capturedType = capture(owntype); 3090 attribExpr(tree.rhs, env, owntype); 3091 result = check(tree, capturedType, VAL, resultInfo); 3092 } 3093 3094 public void visitAssignop(JCAssignOp tree) { 3095 // Attribute arguments. 3096 Type owntype = attribTree(tree.lhs, env, varInfo); 3097 Type operand = attribExpr(tree.rhs, env); 3098 // Find operator. 3099 Symbol operator = tree.operator = rs.resolveBinaryOperator( 3100 tree.pos(), tree.getTag().noAssignOp(), env, 3101 owntype, operand); 3102 3103 if (operator.kind == MTH && 3104 !owntype.isErroneous() && 3105 !operand.isErroneous()) { 3106 chk.checkOperator(tree.pos(), 3107 (OperatorSymbol)operator, 3108 tree.getTag().noAssignOp(), 3109 owntype, 3110 operand); 3111 chk.checkDivZero(tree.rhs.pos(), operator, operand); 3112 chk.checkCastable(tree.rhs.pos(), 3113 operator.type.getReturnType(), 3114 owntype); 3115 } 3116 result = check(tree, owntype, VAL, resultInfo); 3117 } 3118 3119 public void visitUnary(JCUnary tree) { 3120 // Attribute arguments. 3121 Type argtype = (tree.getTag().isIncOrDecUnaryOp()) 3122 ? attribTree(tree.arg, env, varInfo) 3123 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env)); 3124 3125 // Find operator. 3126 Symbol operator = tree.operator = 3127 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype); 3128 3129 Type owntype = types.createErrorType(tree.type); 3130 if (operator.kind == MTH && 3131 !argtype.isErroneous()) { 3132 owntype = (tree.getTag().isIncOrDecUnaryOp()) 3133 ? tree.arg.type 3134 : operator.type.getReturnType(); 3135 int opc = ((OperatorSymbol)operator).opcode; 3136 3137 // If the argument is constant, fold it. 3138 if (argtype.constValue() != null) { 3139 Type ctype = cfolder.fold1(opc, argtype); 3140 if (ctype != null) { 3141 owntype = cfolder.coerce(ctype, owntype); 3142 } 3143 } 3144 } 3145 result = check(tree, owntype, VAL, resultInfo); 3146 } 3147 3148 public void visitBinary(JCBinary tree) { 3149 // Attribute arguments. 3150 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env)); 3151 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env)); 3152 3153 // Find operator. 3154 Symbol operator = tree.operator = 3155 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right); 3156 3157 Type owntype = types.createErrorType(tree.type); 3158 if (operator.kind == MTH && 3159 !left.isErroneous() && 3160 !right.isErroneous()) { 3161 owntype = operator.type.getReturnType(); 3162 // This will figure out when unboxing can happen and 3163 // choose the right comparison operator. 3164 int opc = chk.checkOperator(tree.lhs.pos(), 3165 (OperatorSymbol)operator, 3166 tree.getTag(), 3167 left, 3168 right); 3169 3170 // If both arguments are constants, fold them. 3171 if (left.constValue() != null && right.constValue() != null) { 3172 Type ctype = cfolder.fold2(opc, left, right); 3173 if (ctype != null) { 3174 owntype = cfolder.coerce(ctype, owntype); 3175 } 3176 } 3177 3178 // Check that argument types of a reference ==, != are 3179 // castable to each other, (JLS 15.21). Note: unboxing 3180 // comparisons will not have an acmp* opc at this point. 3181 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) { 3182 if (!types.isEqualityComparable(left, right, 3183 new Warner(tree.pos()))) { 3184 log.error(tree.pos(), "incomparable.types", left, right); 3185 } 3186 } 3187 3188 chk.checkDivZero(tree.rhs.pos(), operator, right); 3189 } 3190 result = check(tree, owntype, VAL, resultInfo); 3191 } 3192 3193 public void visitTypeCast(final JCTypeCast tree) { 3194 Type clazztype; 3195 try { 3196 annotate.enterStart(); 3197 clazztype = attribType(tree.clazz, env); 3198 annotate.annotateTypeLater(tree.clazz, env, env.info.scope.owner, 3199 tree.pos(), annotate.castCreator(tree.pos)); 3200 } finally { 3201 annotate.enterDone(); 3202 } 3203 chk.validate(tree.clazz, env, false); 3204 //a fresh environment is required for 292 inference to work properly --- 3205 //see Infer.instantiatePolymorphicSignatureInstance() 3206 Env<AttrContext> localEnv = env.dup(tree); 3207 //should we propagate the target type? 3208 final ResultInfo castInfo; 3209 JCExpression expr = TreeInfo.skipParens(tree.expr); 3210 boolean isPoly = allowPoly && (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE)); 3211 if (isPoly) { 3212 //expression is a poly - we need to propagate target type info 3213 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) { 3214 @Override 3215 public boolean compatible(Type found, Type req, Warner warn) { 3216 return types.isCastable(found, req, warn); 3217 } 3218 }); 3219 } else { 3220 //standalone cast - target-type info is not propagated 3221 castInfo = unknownExprInfo; 3222 } 3223 Type exprtype = attribTree(tree.expr, localEnv, castInfo); 3224 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype); 3225 if (exprtype.constValue() != null) 3226 owntype = cfolder.coerce(exprtype, owntype); 3227 result = check(tree, capture(owntype), VAL, resultInfo); 3228 if (!isPoly) 3229 chk.checkRedundantCast(localEnv, tree); 3230 } 3231 3232 public void visitTypeTest(JCInstanceOf tree) { 3233 Type exprtype = chk.checkNullOrRefType( 3234 tree.expr.pos(), attribExpr(tree.expr, env)); 3235 Type clazztype; 3236 try { 3237 annotate.enterStart(); 3238 clazztype = attribType(tree.clazz, env); 3239 annotate.annotateTypeLater(tree.clazz, env, env.info.scope.owner, tree.pos(), 3240 annotate.instanceOfCreator(tree.pos)); 3241 } finally { 3242 annotate.enterDone(); 3243 } 3244 3245 if (!clazztype.hasTag(TYPEVAR)) { 3246 clazztype = chk.checkClassOrArrayType(tree.clazz.pos(), clazztype); 3247 } 3248 if (!clazztype.isErroneous() && !types.isReifiable(clazztype)) { 3249 log.error(tree.clazz.pos(), "illegal.generic.type.for.instof"); 3250 clazztype = types.createErrorType(clazztype); 3251 } 3252 chk.validate(tree.clazz, env, false); 3253 chk.checkCastable(tree.expr.pos(), exprtype, clazztype); 3254 result = check(tree, syms.booleanType, VAL, resultInfo); 3255 } 3256 3257 public void visitIndexed(JCArrayAccess tree) { 3258 Type owntype = types.createErrorType(tree.type); 3259 Type atype = attribExpr(tree.indexed, env); 3260 attribExpr(tree.index, env, syms.intType); 3261 if (types.isArray(atype)) 3262 owntype = types.elemtype(atype); 3263 else if (!atype.hasTag(ERROR)) 3264 log.error(tree.pos(), "array.req.but.found", atype); 3265 if ((pkind() & VAR) == 0) owntype = capture(owntype); 3266 result = check(tree, owntype, VAR, resultInfo); 3267 } 3268 3269 public void visitIdent(JCIdent tree) { 3270 Symbol sym; 3271 3272 // Find symbol 3273 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) { 3274 // If we are looking for a method, the prototype `pt' will be a 3275 // method type with the type of the call's arguments as parameters. 3276 env.info.pendingResolutionPhase = null; 3277 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments()); 3278 } else if (tree.sym != null && tree.sym.kind != VAR) { 3279 sym = tree.sym; 3280 } else { 3281 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind()); 3282 } 3283 tree.sym = sym; 3284 3285 // (1) Also find the environment current for the class where 3286 // sym is defined (`symEnv'). 3287 // Only for pre-tiger versions (1.4 and earlier): 3288 // (2) Also determine whether we access symbol out of an anonymous 3289 // class in a this or super call. This is illegal for instance 3290 // members since such classes don't carry a this$n link. 3291 // (`noOuterThisPath'). 3292 Env<AttrContext> symEnv = env; 3293 boolean noOuterThisPath = false; 3294 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class 3295 (sym.kind & (VAR | MTH | TYP)) != 0 && 3296 sym.owner.kind == TYP && 3297 tree.name != names._this && tree.name != names._super) { 3298 3299 // Find environment in which identifier is defined. 3300 while (symEnv.outer != null && 3301 !sym.isMemberOf(symEnv.enclClass.sym, types)) { 3302 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0) 3303 noOuterThisPath = false; 3304 symEnv = symEnv.outer; 3305 } 3306 } 3307 3308 // If symbol is a variable, ... 3309 if (sym.kind == VAR) { 3310 VarSymbol v = (VarSymbol)sym; 3311 3312 // ..., evaluate its initializer, if it has one, and check for 3313 // illegal forward reference. 3314 checkInit(tree, env, v, false); 3315 3316 // If we are expecting a variable (as opposed to a value), check 3317 // that the variable is assignable in the current environment. 3318 if (pkind() == VAR) 3319 checkAssignable(tree.pos(), v, null, env); 3320 } 3321 3322 // In a constructor body, 3323 // if symbol is a field or instance method, check that it is 3324 // not accessed before the supertype constructor is called. 3325 if ((symEnv.info.isSelfCall || noOuterThisPath) && 3326 (sym.kind & (VAR | MTH)) != 0 && 3327 sym.owner.kind == TYP && 3328 (sym.flags() & STATIC) == 0) { 3329 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env)); 3330 } 3331 Env<AttrContext> env1 = env; 3332 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) { 3333 // If the found symbol is inaccessible, then it is 3334 // accessed through an enclosing instance. Locate this 3335 // enclosing instance: 3336 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym)) 3337 env1 = env1.outer; 3338 } 3339 3340 if (env.info.isSerializable) { 3341 chk.checkElemAccessFromSerializableLambda(tree); 3342 } 3343 3344 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo); 3345 } 3346 3347 /** Report dependencies. 3348 * @param from The enclosing class sym 3349 * @param to The found identifier that the class depends on. 3350 */ 3351 public void reportDependence(Symbol from, Symbol to) { 3352 // Override if you want to collect the reported dependencies. 3353 } 3354 3355 public void visitSelect(JCFieldAccess tree) { 3356 // Determine the expected kind of the qualifier expression. 3357 int skind = 0; 3358 if (tree.name == names._this || tree.name == names._super || 3359 tree.name == names._class) 3360 { 3361 skind = TYP; 3362 } else { 3363 if ((pkind() & PCK) != 0) skind = skind | PCK; 3364 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK; 3365 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP; 3366 } 3367 3368 // Attribute the qualifier expression, and determine its symbol (if any). 3369 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly)); 3370 if ((pkind() & (PCK | TYP)) == 0) 3371 site = capture(site); // Capture field access 3372 3373 if (skind == TYP) { 3374 // If the qualifier is a type, annotate it 3375 annotate.annotateTypeLater(tree, env, env.info.scope.owner, 3376 tree.pos(), annotate.errorCreator); 3377 Type elt = site; 3378 // don't allow T.class T[].class, etc 3379 while (elt.hasTag(ARRAY)) 3380 elt = ((ArrayType)elt).elemtype; 3381 if (elt.hasTag(TYPEVAR)) { 3382 log.error(tree.pos(), "type.var.cant.be.deref"); 3383 result = types.createErrorType(tree.type); 3384 return; 3385 } 3386 } 3387 3388 // If qualifier symbol is a type or `super', assert `selectSuper' 3389 // for the selection. This is relevant for determining whether 3390 // protected symbols are accessible. 3391 Symbol sitesym = TreeInfo.symbol(tree.selected); 3392 boolean selectSuperPrev = env.info.selectSuper; 3393 env.info.selectSuper = 3394 sitesym != null && 3395 sitesym.name == names._super; 3396 3397 // Determine the symbol represented by the selection. 3398 env.info.pendingResolutionPhase = null; 3399 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo); 3400 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) { 3401 site = capture(site); 3402 sym = selectSym(tree, sitesym, site, env, resultInfo); 3403 } 3404 boolean varArgs = env.info.lastResolveVarargs(); 3405 tree.sym = sym; 3406 3407 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) { 3408 while (site.hasTag(TYPEVAR)) site = site.getUpperBound(); 3409 site = capture(site); 3410 } 3411 3412 // If that symbol is a variable, ... 3413 if (sym.kind == VAR) { 3414 VarSymbol v = (VarSymbol)sym; 3415 3416 // ..., evaluate its initializer, if it has one, and check for 3417 // illegal forward reference. 3418 checkInit(tree, env, v, true); 3419 3420 // If we are expecting a variable (as opposed to a value), check 3421 // that the variable is assignable in the current environment. 3422 if (pkind() == VAR) 3423 checkAssignable(tree.pos(), v, tree.selected, env); 3424 } 3425 3426 if (sitesym != null && 3427 sitesym.kind == VAR && 3428 ((VarSymbol)sitesym).isResourceVariable() && 3429 sym.kind == MTH && 3430 sym.name.equals(names.close) && 3431 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) && 3432 env.info.lint.isEnabled(LintCategory.TRY)) { 3433 log.warning(LintCategory.TRY, tree, "try.explicit.close.call"); 3434 } 3435 3436 // Disallow selecting a type from an expression 3437 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) { 3438 tree.type = check(tree.selected, pt(), 3439 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt())); 3440 } 3441 3442 if (isType(sitesym)) { 3443 if (sym.name == names._this) { 3444 // If `C' is the currently compiled class, check that 3445 // C.this' does not appear in a call to a super(...) 3446 if (env.info.isSelfCall && 3447 site.tsym == env.enclClass.sym) { 3448 chk.earlyRefError(tree.pos(), sym); 3449 } 3450 } else { 3451 // Check if type-qualified fields or methods are static (JLS) 3452 if ((sym.flags() & STATIC) == 0 && 3453 !env.next.tree.hasTag(REFERENCE) && 3454 sym.name != names._super && 3455 (sym.kind == VAR || sym.kind == MTH)) { 3456 rs.accessBase(rs.new StaticError(sym), 3457 tree.pos(), site, sym.name, true); 3458 } 3459 } 3460 if (!allowStaticInterfaceMethods && sitesym.isInterface() && 3461 sym.isStatic() && sym.kind == MTH) { 3462 log.error(tree.pos(), "static.intf.method.invoke.not.supported.in.source", sourceName); 3463 } 3464 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) { 3465 // If the qualified item is not a type and the selected item is static, report 3466 // a warning. Make allowance for the class of an array type e.g. Object[].class) 3467 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner); 3468 } 3469 3470 // If we are selecting an instance member via a `super', ... 3471 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) { 3472 3473 // Check that super-qualified symbols are not abstract (JLS) 3474 rs.checkNonAbstract(tree.pos(), sym); 3475 3476 if (site.isRaw()) { 3477 // Determine argument types for site. 3478 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym); 3479 if (site1 != null) site = site1; 3480 } 3481 } 3482 3483 if (env.info.isSerializable) { 3484 chk.checkElemAccessFromSerializableLambda(tree); 3485 } 3486 3487 env.info.selectSuper = selectSuperPrev; 3488 result = checkId(tree, site, sym, env, resultInfo); 3489 3490 if ((tree.sym.kind & TYP) != 0) { 3491 reportDependence(env.enclClass.sym, tree.sym); 3492 } 3493 } 3494 //where 3495 /** Determine symbol referenced by a Select expression, 3496 * 3497 * @param tree The select tree. 3498 * @param site The type of the selected expression, 3499 * @param env The current environment. 3500 * @param resultInfo The current result. 3501 */ 3502 private Symbol selectSym(JCFieldAccess tree, 3503 Symbol location, 3504 Type site, 3505 Env<AttrContext> env, 3506 ResultInfo resultInfo) { 3507 DiagnosticPosition pos = tree.pos(); 3508 Name name = tree.name; 3509 switch (site.getTag()) { 3510 case PACKAGE: 3511 return rs.accessBase( 3512 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind), 3513 pos, location, site, name, true); 3514 case ARRAY: 3515 case CLASS: 3516 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) { 3517 return rs.resolveQualifiedMethod( 3518 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments()); 3519 } else if (name == names._this || name == names._super) { 3520 return rs.resolveSelf(pos, env, site.tsym, name); 3521 } else if (name == names._class) { 3522 // In this case, we have already made sure in 3523 // visitSelect that qualifier expression is a type. 3524 Type t = syms.classType; 3525 List<Type> typeargs = List.of(types.erasure(site)); 3526 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym); 3527 return new VarSymbol( 3528 STATIC | PUBLIC | FINAL, names._class, t, site.tsym); 3529 } else { 3530 // We are seeing a plain identifier as selector. 3531 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind); 3532 if ((resultInfo.pkind & ERRONEOUS) == 0) 3533 sym = rs.accessBase(sym, pos, location, site, name, true); 3534 return sym; 3535 } 3536 case WILDCARD: 3537 throw new AssertionError(tree); 3538 case TYPEVAR: 3539 // Normally, site.getUpperBound() shouldn't be null. 3540 // It should only happen during memberEnter/attribBase 3541 // when determining the super type which *must* beac 3542 // done before attributing the type variables. In 3543 // other words, we are seeing this illegal program: 3544 // class B<T> extends A<T.foo> {} 3545 Symbol sym = (site.getUpperBound() != null) 3546 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo) 3547 : null; 3548 if (sym == null) { 3549 log.error(pos, "type.var.cant.be.deref"); 3550 return syms.errSymbol; 3551 } else { 3552 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ? 3553 rs.new AccessError(env, site, sym) : 3554 sym; 3555 rs.accessBase(sym2, pos, location, site, name, true); 3556 return sym; 3557 } 3558 case ERROR: 3559 // preserve identifier names through errors 3560 return types.createErrorType(name, site.tsym, site).tsym; 3561 default: 3562 // The qualifier expression is of a primitive type -- only 3563 // .class is allowed for these. 3564 if (name == names._class) { 3565 // In this case, we have already made sure in Select that 3566 // qualifier expression is a type. 3567 Type t = syms.classType; 3568 Type arg = types.boxedClass(site).type; 3569 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym); 3570 return new VarSymbol( 3571 STATIC | PUBLIC | FINAL, names._class, t, site.tsym); 3572 } else { 3573 log.error(pos, "cant.deref", site); 3574 return syms.errSymbol; 3575 } 3576 } 3577 } 3578 3579 /** Determine type of identifier or select expression and check that 3580 * (1) the referenced symbol is not deprecated 3581 * (2) the symbol's type is safe (@see checkSafe) 3582 * (3) if symbol is a variable, check that its type and kind are 3583 * compatible with the prototype and protokind. 3584 * (4) if symbol is an instance field of a raw type, 3585 * which is being assigned to, issue an unchecked warning if its 3586 * type changes under erasure. 3587 * (5) if symbol is an instance method of a raw type, issue an 3588 * unchecked warning if its argument types change under erasure. 3589 * If checks succeed: 3590 * If symbol is a constant, return its constant type 3591 * else if symbol is a method, return its result type 3592 * otherwise return its type. 3593 * Otherwise return errType. 3594 * 3595 * @param tree The syntax tree representing the identifier 3596 * @param site If this is a select, the type of the selected 3597 * expression, otherwise the type of the current class. 3598 * @param sym The symbol representing the identifier. 3599 * @param env The current environment. 3600 * @param resultInfo The expected result 3601 */ 3602 Type checkId(JCTree tree, 3603 Type site, 3604 Symbol sym, 3605 Env<AttrContext> env, 3606 ResultInfo resultInfo) { 3607 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ? 3608 checkMethodId(tree, site, sym, env, resultInfo) : 3609 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo); 3610 } 3611 3612 Type checkMethodId(JCTree tree, 3613 Type site, 3614 Symbol sym, 3615 Env<AttrContext> env, 3616 ResultInfo resultInfo) { 3617 boolean isPolymorhicSignature = 3618 (sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) != 0; 3619 return isPolymorhicSignature ? 3620 checkSigPolyMethodId(tree, site, sym, env, resultInfo) : 3621 checkMethodIdInternal(tree, site, sym, env, resultInfo); 3622 } 3623 3624 Type checkSigPolyMethodId(JCTree tree, 3625 Type site, 3626 Symbol sym, 3627 Env<AttrContext> env, 3628 ResultInfo resultInfo) { 3629 //recover original symbol for signature polymorphic methods 3630 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo); 3631 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC; 3632 return sym.type; 3633 } 3634 3635 Type checkMethodIdInternal(JCTree tree, 3636 Type site, 3637 Symbol sym, 3638 Env<AttrContext> env, 3639 ResultInfo resultInfo) { 3640 if ((resultInfo.pkind & POLY) != 0) { 3641 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase)); 3642 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo); 3643 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase)); 3644 return owntype; 3645 } else { 3646 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo); 3647 } 3648 } 3649 3650 Type checkIdInternal(JCTree tree, 3651 Type site, 3652 Symbol sym, 3653 Type pt, 3654 Env<AttrContext> env, 3655 ResultInfo resultInfo) { 3656 if (pt.isErroneous()) { 3657 return types.createErrorType(site); 3658 } 3659 Type owntype; // The computed type of this identifier occurrence. 3660 switch (sym.kind) { 3661 case TYP: 3662 // For types, the computed type equals the symbol's type, 3663 // except for two situations: 3664 owntype = sym.type; 3665 if (owntype.hasTag(CLASS)) { 3666 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym); 3667 Type ownOuter = owntype.getEnclosingType(); 3668 3669 // (a) If the symbol's type is parameterized, erase it 3670 // because no type parameters were given. 3671 // We recover generic outer type later in visitTypeApply. 3672 if (owntype.tsym.type.getTypeArguments().nonEmpty()) { 3673 owntype = types.erasure(owntype); 3674 } 3675 3676 // (b) If the symbol's type is an inner class, then 3677 // we have to interpret its outer type as a superclass 3678 // of the site type. Example: 3679 // 3680 // class Tree<A> { class Visitor { ... } } 3681 // class PointTree extends Tree<Point> { ... } 3682 // ...PointTree.Visitor... 3683 // 3684 // Then the type of the last expression above is 3685 // Tree<Point>.Visitor. 3686 else if (ownOuter.hasTag(CLASS) && site != ownOuter) { 3687 Type normOuter = site; 3688 if (normOuter.hasTag(CLASS)) { 3689 normOuter = types.asEnclosingSuper(site, ownOuter.tsym); 3690 } 3691 if (normOuter == null) // perhaps from an import 3692 normOuter = types.erasure(ownOuter); 3693 if (normOuter != ownOuter) 3694 owntype = new ClassType( 3695 normOuter, List.<Type>nil(), owntype.tsym, 3696 owntype.getAnnotationMirrors()); 3697 } 3698 } 3699 break; 3700 case VAR: 3701 VarSymbol v = (VarSymbol)sym; 3702 // Test (4): if symbol is an instance field of a raw type, 3703 // which is being assigned to, issue an unchecked warning if 3704 // its type changes under erasure. 3705 if (resultInfo.pkind == VAR && 3706 v.owner.kind == TYP && 3707 (v.flags() & STATIC) == 0 && 3708 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) { 3709 Type s = types.asOuterSuper(site, v.owner); 3710 if (s != null && 3711 s.isRaw() && 3712 !types.isSameType(v.type, v.erasure(types))) { 3713 chk.warnUnchecked(tree.pos(), 3714 "unchecked.assign.to.var", 3715 v, s); 3716 } 3717 } 3718 // The computed type of a variable is the type of the 3719 // variable symbol, taken as a member of the site type. 3720 owntype = (sym.owner.kind == TYP && 3721 sym.name != names._this && sym.name != names._super) 3722 ? types.memberType(site, sym) 3723 : sym.type; 3724 3725 // If the variable is a constant, record constant value in 3726 // computed type. 3727 if (v.getConstValue() != null && isStaticReference(tree)) 3728 owntype = owntype.constType(v.getConstValue()); 3729 3730 if (resultInfo.pkind == VAL) { 3731 owntype = capture(owntype); // capture "names as expressions" 3732 } 3733 break; 3734 case MTH: { 3735 owntype = checkMethod(site, sym, 3736 new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext), 3737 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(), 3738 resultInfo.pt.getTypeArguments()); 3739 break; 3740 } 3741 case PCK: case ERR: 3742 owntype = sym.type; 3743 break; 3744 default: 3745 throw new AssertionError("unexpected kind: " + sym.kind + 3746 " in tree " + tree); 3747 } 3748 3749 // Test (1): emit a `deprecation' warning if symbol is deprecated. 3750 // (for constructors, the error was given when the constructor was 3751 // resolved) 3752 3753 if (sym.name != names.init) { 3754 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym); 3755 chk.checkSunAPI(tree.pos(), sym); 3756 chk.checkProfile(tree.pos(), sym); 3757 } 3758 3759 // Test (3): if symbol is a variable, check that its type and 3760 // kind are compatible with the prototype and protokind. 3761 return check(tree, owntype, sym.kind, resultInfo); 3762 } 3763 3764 /** Check that variable is initialized and evaluate the variable's 3765 * initializer, if not yet done. Also check that variable is not 3766 * referenced before it is defined. 3767 * @param tree The tree making up the variable reference. 3768 * @param env The current environment. 3769 * @param v The variable's symbol. 3770 */ 3771 private void checkInit(JCTree tree, 3772 Env<AttrContext> env, 3773 VarSymbol v, 3774 boolean onlyWarning) { 3775// System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " + 3776// tree.pos + " " + v.pos + " " + 3777// Resolve.isStatic(env));//DEBUG 3778 3779 // A forward reference is diagnosed if the declaration position 3780 // of the variable is greater than the current tree position 3781 // and the tree and variable definition occur in the same class 3782 // definition. Note that writes don't count as references. 3783 // This check applies only to class and instance 3784 // variables. Local variables follow different scope rules, 3785 // and are subject to definite assignment checking. 3786 if ((env.info.enclVar == v || v.pos > tree.pos) && 3787 v.owner.kind == TYP && 3788 enclosingInitEnv(env) != null && 3789 v.owner == env.info.scope.owner.enclClass() && 3790 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) && 3791 (!env.tree.hasTag(ASSIGN) || 3792 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) { 3793 String suffix = (env.info.enclVar == v) ? 3794 "self.ref" : "forward.ref"; 3795 if (!onlyWarning || isStaticEnumField(v)) { 3796 log.error(tree.pos(), "illegal." + suffix); 3797 } else if (useBeforeDeclarationWarning) { 3798 log.warning(tree.pos(), suffix, v); 3799 } 3800 } 3801 3802 v.getConstValue(); // ensure initializer is evaluated 3803 3804 checkEnumInitializer(tree, env, v); 3805 } 3806 3807 /** 3808 * Returns the enclosing init environment associated with this env (if any). An init env 3809 * can be either a field declaration env or a static/instance initializer env. 3810 */ 3811 Env<AttrContext> enclosingInitEnv(Env<AttrContext> env) { 3812 while (true) { 3813 switch (env.tree.getTag()) { 3814 case VARDEF: 3815 JCVariableDecl vdecl = (JCVariableDecl)env.tree; 3816 if (vdecl.sym.owner.kind == TYP) { 3817 //field 3818 return env; 3819 } 3820 break; 3821 case BLOCK: 3822 if (env.next.tree.hasTag(CLASSDEF)) { 3823 //instance/static initializer 3824 return env; 3825 } 3826 break; 3827 case METHODDEF: 3828 case CLASSDEF: 3829 case TOPLEVEL: 3830 return null; 3831 } 3832 Assert.checkNonNull(env.next); 3833 env = env.next; 3834 } 3835 } 3836 3837 /** 3838 * Check for illegal references to static members of enum. In 3839 * an enum type, constructors and initializers may not 3840 * reference its static members unless they are constant. 3841 * 3842 * @param tree The tree making up the variable reference. 3843 * @param env The current environment. 3844 * @param v The variable's symbol. 3845 * @jls section 8.9 Enums 3846 */ 3847 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) { 3848 // JLS: 3849 // 3850 // "It is a compile-time error to reference a static field 3851 // of an enum type that is not a compile-time constant 3852 // (15.28) from constructors, instance initializer blocks, 3853 // or instance variable initializer expressions of that 3854 // type. It is a compile-time error for the constructors, 3855 // instance initializer blocks, or instance variable 3856 // initializer expressions of an enum constant e to refer 3857 // to itself or to an enum constant of the same type that 3858 // is declared to the right of e." 3859 if (isStaticEnumField(v)) { 3860 ClassSymbol enclClass = env.info.scope.owner.enclClass(); 3861 3862 if (enclClass == null || enclClass.owner == null) 3863 return; 3864 3865 // See if the enclosing class is the enum (or a 3866 // subclass thereof) declaring v. If not, this 3867 // reference is OK. 3868 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type)) 3869 return; 3870 3871 // If the reference isn't from an initializer, then 3872 // the reference is OK. 3873 if (!Resolve.isInitializer(env)) 3874 return; 3875 3876 log.error(tree.pos(), "illegal.enum.static.ref"); 3877 } 3878 } 3879 3880 /** Is the given symbol a static, non-constant field of an Enum? 3881 * Note: enum literals should not be regarded as such 3882 */ 3883 private boolean isStaticEnumField(VarSymbol v) { 3884 return Flags.isEnum(v.owner) && 3885 Flags.isStatic(v) && 3886 !Flags.isConstant(v) && 3887 v.name != names._class; 3888 } 3889 3890 Warner noteWarner = new Warner(); 3891 3892 /** 3893 * Check that method arguments conform to its instantiation. 3894 **/ 3895 public Type checkMethod(Type site, 3896 final Symbol sym, 3897 ResultInfo resultInfo, 3898 Env<AttrContext> env, 3899 final List<JCExpression> argtrees, 3900 List<Type> argtypes, 3901 List<Type> typeargtypes) { 3902 // Test (5): if symbol is an instance method of a raw type, issue 3903 // an unchecked warning if its argument types change under erasure. 3904 if ((sym.flags() & STATIC) == 0 && 3905 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) { 3906 Type s = types.asOuterSuper(site, sym.owner); 3907 if (s != null && s.isRaw() && 3908 !types.isSameTypes(sym.type.getParameterTypes(), 3909 sym.erasure(types).getParameterTypes())) { 3910 chk.warnUnchecked(env.tree.pos(), 3911 "unchecked.call.mbr.of.raw.type", 3912 sym, s); 3913 } 3914 } 3915 3916 if (env.info.defaultSuperCallSite != null) { 3917 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) { 3918 if (!sup.tsym.isSubClass(sym.enclClass(), types) || 3919 types.isSameType(sup, env.info.defaultSuperCallSite)) continue; 3920 List<MethodSymbol> icand_sup = 3921 types.interfaceCandidates(sup, (MethodSymbol)sym); 3922 if (icand_sup.nonEmpty() && 3923 icand_sup.head != sym && 3924 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) { 3925 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite, 3926 diags.fragment("overridden.default", sym, sup)); 3927 break; 3928 } 3929 } 3930 env.info.defaultSuperCallSite = null; 3931 } 3932 3933 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) { 3934 JCMethodInvocation app = (JCMethodInvocation)env.tree; 3935 if (app.meth.hasTag(SELECT) && 3936 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) { 3937 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site); 3938 } 3939 } 3940 3941 // Compute the identifier's instantiated type. 3942 // For methods, we need to compute the instance type by 3943 // Resolve.instantiate from the symbol's type as well as 3944 // any type arguments and value arguments. 3945 noteWarner.clear(); 3946 try { 3947 Type owntype = rs.checkMethod( 3948 env, 3949 site, 3950 sym, 3951 resultInfo, 3952 argtypes, 3953 typeargtypes, 3954 noteWarner); 3955 3956 DeferredAttr.DeferredTypeMap checkDeferredMap = 3957 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase); 3958 3959 argtypes = Type.map(argtypes, checkDeferredMap); 3960 3961 if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 3962 chk.warnUnchecked(env.tree.pos(), 3963 "unchecked.meth.invocation.applied", 3964 kindName(sym), 3965 sym.name, 3966 rs.methodArguments(sym.type.getParameterTypes()), 3967 rs.methodArguments(Type.map(argtypes, checkDeferredMap)), 3968 kindName(sym.location()), 3969 sym.location()); 3970 owntype = new MethodType(owntype.getParameterTypes(), 3971 types.erasure(owntype.getReturnType()), 3972 types.erasure(owntype.getThrownTypes()), 3973 syms.methodClass); 3974 } 3975 3976 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(), 3977 resultInfo.checkContext.inferenceContext()); 3978 } catch (Infer.InferenceException ex) { 3979 //invalid target type - propagate exception outwards or report error 3980 //depending on the current check context 3981 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic()); 3982 return types.createErrorType(site); 3983 } catch (Resolve.InapplicableMethodException ex) { 3984 final JCDiagnostic diag = ex.getDiagnostic(); 3985 Resolve.InapplicableSymbolError errSym = rs.new InapplicableSymbolError(null) { 3986 @Override 3987 protected Pair<Symbol, JCDiagnostic> errCandidate() { 3988 return new Pair<>(sym, diag); 3989 } 3990 }; 3991 List<Type> argtypes2 = Type.map(argtypes, 3992 rs.new ResolveDeferredRecoveryMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase)); 3993 JCDiagnostic errDiag = errSym.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR, 3994 env.tree, sym, site, sym.name, argtypes2, typeargtypes); 3995 log.report(errDiag); 3996 return types.createErrorType(site); 3997 } 3998 } 3999 4000 public void visitLiteral(JCLiteral tree) { 4001 result = check( 4002 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo); 4003 } 4004 //where 4005 /** Return the type of a literal with given type tag. 4006 */ 4007 Type litType(TypeTag tag) { 4008 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()]; 4009 } 4010 4011 public void visitTypeIdent(JCPrimitiveTypeTree tree) { 4012 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo); 4013 } 4014 4015 public void visitTypeArray(JCArrayTypeTree tree) { 4016 Type etype = attribType(tree.elemtype, env); 4017 Type type = new ArrayType(etype, syms.arrayClass, Type.noAnnotations); 4018 result = check(tree, type, TYP, resultInfo); 4019 } 4020 4021 /** Visitor method for parameterized types. 4022 * Bound checking is left until later, since types are attributed 4023 * before supertype structure is completely known 4024 */ 4025 public void visitTypeApply(JCTypeApply tree) { 4026 Type owntype = types.createErrorType(tree.type); 4027 4028 // Attribute functor part of application and make sure it's a class. 4029 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env)); 4030 4031 // Attribute type parameters 4032 List<Type> actuals = attribTypes(tree.arguments, env); 4033 4034 if (clazztype.hasTag(CLASS)) { 4035 List<Type> formals = clazztype.tsym.type.getTypeArguments(); 4036 if (actuals.isEmpty()) //diamond 4037 actuals = formals; 4038 4039 if (actuals.length() == formals.length()) { 4040 List<Type> a = actuals; 4041 List<Type> f = formals; 4042 while (a.nonEmpty()) { 4043 a.head = a.head.withTypeVar(f.head); 4044 a = a.tail; 4045 f = f.tail; 4046 } 4047 // Compute the proper generic outer 4048 Type clazzOuter = clazztype.getEnclosingType(); 4049 if (clazzOuter.hasTag(CLASS)) { 4050 Type site; 4051 JCExpression clazz = TreeInfo.typeIn(tree.clazz); 4052 if (clazz.hasTag(IDENT)) { 4053 site = env.enclClass.sym.type; 4054 } else if (clazz.hasTag(SELECT)) { 4055 site = ((JCFieldAccess) clazz).selected.type; 4056 } else throw new AssertionError(""+tree); 4057 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) { 4058 if (site.hasTag(CLASS)) 4059 site = types.asOuterSuper(site, clazzOuter.tsym); 4060 if (site == null) 4061 site = types.erasure(clazzOuter); 4062 clazzOuter = site; 4063 } 4064 } 4065 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym, 4066 clazztype.getAnnotationMirrors()); 4067 } else { 4068 if (formals.length() != 0) { 4069 log.error(tree.pos(), "wrong.number.type.args", 4070 Integer.toString(formals.length())); 4071 } else { 4072 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym); 4073 } 4074 owntype = types.createErrorType(tree.type); 4075 } 4076 } 4077 result = check(tree, owntype, TYP, resultInfo); 4078 } 4079 4080 public void visitTypeUnion(JCTypeUnion tree) { 4081 ListBuffer<Type> multicatchTypes = new ListBuffer<>(); 4082 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed 4083 for (JCExpression typeTree : tree.alternatives) { 4084 Type ctype = attribType(typeTree, env); 4085 ctype = chk.checkType(typeTree.pos(), 4086 chk.checkClassType(typeTree.pos(), ctype), 4087 syms.throwableType); 4088 if (!ctype.isErroneous()) { 4089 //check that alternatives of a union type are pairwise 4090 //unrelated w.r.t. subtyping 4091 if (chk.intersects(ctype, multicatchTypes.toList())) { 4092 for (Type t : multicatchTypes) { 4093 boolean sub = types.isSubtype(ctype, t); 4094 boolean sup = types.isSubtype(t, ctype); 4095 if (sub || sup) { 4096 //assume 'a' <: 'b' 4097 Type a = sub ? ctype : t; 4098 Type b = sub ? t : ctype; 4099 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b); 4100 } 4101 } 4102 } 4103 multicatchTypes.append(ctype); 4104 if (all_multicatchTypes != null) 4105 all_multicatchTypes.append(ctype); 4106 } else { 4107 if (all_multicatchTypes == null) { 4108 all_multicatchTypes = new ListBuffer<>(); 4109 all_multicatchTypes.appendList(multicatchTypes); 4110 } 4111 all_multicatchTypes.append(ctype); 4112 } 4113 } 4114 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo); 4115 if (t.hasTag(CLASS)) { 4116 List<Type> alternatives = 4117 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList(); 4118 t = new UnionClassType((ClassType) t, alternatives); 4119 } 4120 tree.type = result = t; 4121 } 4122 4123 public void visitTypeIntersection(JCTypeIntersection tree) { 4124 attribTypes(tree.bounds, env); 4125 tree.type = result = checkIntersection(tree, tree.bounds); 4126 } 4127 4128 public void visitTypeParameter(JCTypeParameter tree) { 4129 TypeVar typeVar = (TypeVar) tree.type; 4130 4131 if (tree.annotations != null && tree.annotations.nonEmpty()) { 4132 annotateType(tree, tree.annotations); 4133 } 4134 4135 if (!typeVar.bound.isErroneous()) { 4136 //fixup type-parameter bound computed in 'attribTypeVariables' 4137 typeVar.bound = checkIntersection(tree, tree.bounds); 4138 } 4139 } 4140 4141 Type checkIntersection(JCTree tree, List<JCExpression> bounds) { 4142 Set<Type> boundSet = new HashSet<>(); 4143 if (bounds.nonEmpty()) { 4144 // accept class or interface or typevar as first bound. 4145 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false); 4146 boundSet.add(types.erasure(bounds.head.type)); 4147 if (bounds.head.type.isErroneous()) { 4148 return bounds.head.type; 4149 } 4150 else if (bounds.head.type.hasTag(TYPEVAR)) { 4151 // if first bound was a typevar, do not accept further bounds. 4152 if (bounds.tail.nonEmpty()) { 4153 log.error(bounds.tail.head.pos(), 4154 "type.var.may.not.be.followed.by.other.bounds"); 4155 return bounds.head.type; 4156 } 4157 } else { 4158 // if first bound was a class or interface, accept only interfaces 4159 // as further bounds. 4160 for (JCExpression bound : bounds.tail) { 4161 bound.type = checkBase(bound.type, bound, env, false, true, false); 4162 if (bound.type.isErroneous()) { 4163 bounds = List.of(bound); 4164 } 4165 else if (bound.type.hasTag(CLASS)) { 4166 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet); 4167 } 4168 } 4169 } 4170 } 4171 4172 if (bounds.length() == 0) { 4173 return syms.objectType; 4174 } else if (bounds.length() == 1) { 4175 return bounds.head.type; 4176 } else { 4177 Type owntype = types.makeCompoundType(TreeInfo.types(bounds)); 4178 // ... the variable's bound is a class type flagged COMPOUND 4179 // (see comment for TypeVar.bound). 4180 // In this case, generate a class tree that represents the 4181 // bound class, ... 4182 JCExpression extending; 4183 List<JCExpression> implementing; 4184 if (!bounds.head.type.isInterface()) { 4185 extending = bounds.head; 4186 implementing = bounds.tail; 4187 } else { 4188 extending = null; 4189 implementing = bounds; 4190 } 4191 JCClassDecl cd = make.at(tree).ClassDef( 4192 make.Modifiers(PUBLIC | ABSTRACT), 4193 names.empty, List.<JCTypeParameter>nil(), 4194 extending, implementing, List.<JCTree>nil()); 4195 4196 ClassSymbol c = (ClassSymbol)owntype.tsym; 4197 Assert.check((c.flags() & COMPOUND) != 0); 4198 cd.sym = c; 4199 c.sourcefile = env.toplevel.sourcefile; 4200 4201 // ... and attribute the bound class 4202 c.flags_field |= UNATTRIBUTED; 4203 Env<AttrContext> cenv = enter.classEnv(cd, env); 4204 typeEnvs.put(c, cenv); 4205 attribClass(c); 4206 return owntype; 4207 } 4208 } 4209 4210 public void visitWildcard(JCWildcard tree) { 4211 //- System.err.println("visitWildcard("+tree+");");//DEBUG 4212 Type type = (tree.kind.kind == BoundKind.UNBOUND) 4213 ? syms.objectType 4214 : attribType(tree.inner, env); 4215 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type), 4216 tree.kind.kind, 4217 syms.boundClass, 4218 Type.noAnnotations), 4219 TYP, resultInfo); 4220 } 4221 4222 public void visitAnnotation(JCAnnotation tree) { 4223 Assert.error("should be handled in Annotate"); 4224 } 4225 4226 /* This needs to be removed or otherwise changed, as it implicitly 4227 * relies on the annotated types having previously been visited by 4228 * Annotate.TypeAnnotate. 4229 */ 4230 public void visitAnnotatedType(JCAnnotatedType tree) { 4231 Type underlyingType = attribTree(tree.getUnderlyingType(), env, 4232 resultInfo); 4233 this.attribAnnotationTypes(tree.annotations, env); 4234 annotateType(tree, tree.annotations); 4235 result = tree.type = underlyingType; 4236 } 4237 4238 /** 4239 * Apply the annotations to the particular type. 4240 */ 4241 public void annotateType(final JCTree tree, final List<JCAnnotation> annotations) { 4242 annotate.typeAnnotation(new Annotate.Worker() { 4243 @Override 4244 public String toString() { 4245 return "annotate " + annotations + " onto " + tree; 4246 } 4247 @Override 4248 public void run() { 4249 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations); 4250 Assert.check(annotations.size() == compounds.size()); 4251 if (!tree.type.hasTag(TypeTag.PACKAGE)) { 4252 tree.type = tree.type.annotatedType(compounds); 4253 } 4254 } 4255 }); 4256 } 4257 4258 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) { 4259 if (annotations.isEmpty()) { 4260 return List.nil(); 4261 } 4262 4263 ListBuffer<Attribute.TypeCompound> buf = new ListBuffer<>(); 4264 for (JCAnnotation anno : annotations) { 4265 Assert.checkNonNull(anno.attribute); 4266 buf.append((Attribute.TypeCompound) anno.attribute); 4267 } 4268 return buf.toList(); 4269 } 4270 4271 public void visitErroneous(JCErroneous tree) { 4272 if (tree.errs != null) 4273 for (JCTree err : tree.errs) 4274 attribTree(err, env, new ResultInfo(ERR, pt())); 4275 result = tree.type = syms.errType; 4276 } 4277 4278 /** Default visitor method for all other trees. 4279 */ 4280 public void visitTree(JCTree tree) { 4281 throw new AssertionError(); 4282 } 4283 4284 /** 4285 * Attribute an env for either a top level tree or class declaration. 4286 */ 4287 public void attrib(Env<AttrContext> env) { 4288 if (env.tree.hasTag(TOPLEVEL)) 4289 attribTopLevel(env); 4290 else 4291 attribClass(env.tree.pos(), env.enclClass.sym); 4292 } 4293 4294 /** 4295 * Attribute a top level tree. These trees are encountered when the 4296 * package declaration has annotations. 4297 */ 4298 public void attribTopLevel(Env<AttrContext> env) { 4299 JCCompilationUnit toplevel = env.toplevel; 4300 try { 4301 annotate.flush(); 4302 } catch (CompletionFailure ex) { 4303 chk.completionError(toplevel.pos(), ex); 4304 } 4305 } 4306 4307 /** Main method: attribute class definition associated with given class symbol. 4308 * reporting completion failures at the given position. 4309 * @param pos The source position at which completion errors are to be 4310 * reported. 4311 * @param c The class symbol whose definition will be attributed. 4312 */ 4313 public void attribClass(DiagnosticPosition pos, ClassSymbol c) { 4314 try { 4315 annotate.flush(); 4316 attribClass(c); 4317 } catch (CompletionFailure ex) { 4318 chk.completionError(pos, ex); 4319 } 4320 } 4321 4322 /** Attribute class definition associated with given class symbol. 4323 * @param c The class symbol whose definition will be attributed. 4324 */ 4325 void attribClass(ClassSymbol c) throws CompletionFailure { 4326 if (c.type.hasTag(ERROR)) return; 4327 4328 // Check for cycles in the inheritance graph, which can arise from 4329 // ill-formed class files. 4330 chk.checkNonCyclic(null, c.type); 4331 4332 Type st = types.supertype(c.type); 4333 if ((c.flags_field & Flags.COMPOUND) == 0) { 4334 // First, attribute superclass. 4335 if (st.hasTag(CLASS)) 4336 attribClass((ClassSymbol)st.tsym); 4337 4338 // Next attribute owner, if it is a class. 4339 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS)) 4340 attribClass((ClassSymbol)c.owner); 4341 } 4342 4343 // The previous operations might have attributed the current class 4344 // if there was a cycle. So we test first whether the class is still 4345 // UNATTRIBUTED. 4346 if ((c.flags_field & UNATTRIBUTED) != 0) { 4347 c.flags_field &= ~UNATTRIBUTED; 4348 4349 // Get environment current at the point of class definition. 4350 Env<AttrContext> env = typeEnvs.get(c); 4351 4352 // The info.lint field in the envs stored in typeEnvs is deliberately uninitialized, 4353 // because the annotations were not available at the time the env was created. Therefore, 4354 // we look up the environment chain for the first enclosing environment for which the 4355 // lint value is set. Typically, this is the parent env, but might be further if there 4356 // are any envs created as a result of TypeParameter nodes. 4357 Env<AttrContext> lintEnv = env; 4358 while (lintEnv.info.lint == null) 4359 lintEnv = lintEnv.next; 4360 4361 // Having found the enclosing lint value, we can initialize the lint value for this class 4362 env.info.lint = lintEnv.info.lint.augment(c); 4363 4364 Lint prevLint = chk.setLint(env.info.lint); 4365 JavaFileObject prev = log.useSource(c.sourcefile); 4366 ResultInfo prevReturnRes = env.info.returnResult; 4367 4368 try { 4369 deferredLintHandler.flush(env.tree); 4370 env.info.returnResult = null; 4371 // java.lang.Enum may not be subclassed by a non-enum 4372 if (st.tsym == syms.enumSym && 4373 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0)) 4374 log.error(env.tree.pos(), "enum.no.subclassing"); 4375 4376 // Enums may not be extended by source-level classes 4377 if (st.tsym != null && 4378 ((st.tsym.flags_field & Flags.ENUM) != 0) && 4379 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) { 4380 log.error(env.tree.pos(), "enum.types.not.extensible"); 4381 } 4382 4383 if (isSerializable(c.type)) { 4384 env.info.isSerializable = true; 4385 } 4386 4387 attribClassBody(env, c); 4388 4389 chk.checkDeprecatedAnnotation(env.tree.pos(), c); 4390 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c); 4391 chk.checkFunctionalInterface((JCClassDecl) env.tree, c); 4392 } finally { 4393 env.info.returnResult = prevReturnRes; 4394 log.useSource(prev); 4395 chk.setLint(prevLint); 4396 } 4397 4398 } 4399 } 4400 4401 public void visitImport(JCImport tree) { 4402 // nothing to do 4403 } 4404 4405 /** Finish the attribution of a class. */ 4406 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) { 4407 JCClassDecl tree = (JCClassDecl)env.tree; 4408 Assert.check(c == tree.sym); 4409 4410 // Validate type parameters, supertype and interfaces. 4411 attribStats(tree.typarams, env); 4412 if (!c.isAnonymous()) { 4413 //already checked if anonymous 4414 chk.validate(tree.typarams, env); 4415 chk.validate(tree.extending, env); 4416 chk.validate(tree.implementing, env); 4417 } 4418 4419 // If this is a non-abstract class, check that it has no abstract 4420 // methods or unimplemented methods of an implemented interface. 4421 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) { 4422 if (!relax) 4423 chk.checkAllDefined(tree.pos(), c); 4424 } 4425 4426 if ((c.flags() & ANNOTATION) != 0) { 4427 if (tree.implementing.nonEmpty()) 4428 log.error(tree.implementing.head.pos(), 4429 "cant.extend.intf.annotation"); 4430 if (tree.typarams.nonEmpty()) 4431 log.error(tree.typarams.head.pos(), 4432 "intf.annotation.cant.have.type.params"); 4433 4434 // If this annotation has a @Repeatable, validate 4435 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym); 4436 if (repeatable != null) { 4437 // get diagnostic position for error reporting 4438 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type); 4439 Assert.checkNonNull(cbPos); 4440 4441 chk.validateRepeatable(c, repeatable, cbPos); 4442 } 4443 } else { 4444 // Check that all extended classes and interfaces 4445 // are compatible (i.e. no two define methods with same arguments 4446 // yet different return types). (JLS 8.4.6.3) 4447 chk.checkCompatibleSupertypes(tree.pos(), c.type); 4448 if (allowDefaultMethods) { 4449 chk.checkDefaultMethodClashes(tree.pos(), c.type); 4450 } 4451 } 4452 4453 // Check that class does not import the same parameterized interface 4454 // with two different argument lists. 4455 chk.checkClassBounds(tree.pos(), c.type); 4456 4457 tree.type = c.type; 4458 4459 for (List<JCTypeParameter> l = tree.typarams; 4460 l.nonEmpty(); l = l.tail) { 4461 Assert.checkNonNull(env.info.scope.findFirst(l.head.name)); 4462 } 4463 4464 // Check that a generic class doesn't extend Throwable 4465 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType)) 4466 log.error(tree.extending.pos(), "generic.throwable"); 4467 4468 // Check that all methods which implement some 4469 // method conform to the method they implement. 4470 chk.checkImplementations(tree); 4471 4472 //check that a resource implementing AutoCloseable cannot throw InterruptedException 4473 checkAutoCloseable(tree.pos(), env, c.type); 4474 4475 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 4476 // Attribute declaration 4477 attribStat(l.head, env); 4478 // Check that declarations in inner classes are not static (JLS 8.1.2) 4479 // Make an exception for static constants. 4480 if (c.owner.kind != PCK && 4481 ((c.flags() & STATIC) == 0 || c.name == names.empty) && 4482 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) { 4483 Symbol sym = null; 4484 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym; 4485 if (sym == null || 4486 sym.kind != VAR || 4487 ((VarSymbol) sym).getConstValue() == null) 4488 log.error(l.head.pos(), "icls.cant.have.static.decl", c); 4489 } 4490 } 4491 4492 // Check for cycles among non-initial constructors. 4493 chk.checkCyclicConstructors(tree); 4494 4495 // Check for cycles among annotation elements. 4496 chk.checkNonCyclicElements(tree); 4497 4498 // Check for proper use of serialVersionUID 4499 if (env.info.lint.isEnabled(LintCategory.SERIAL) && 4500 isSerializable(c.type) && 4501 (c.flags() & Flags.ENUM) == 0 && 4502 checkForSerial(c)) { 4503 checkSerialVersionUID(tree, c); 4504 } 4505 } 4506 // where 4507 boolean checkForSerial(ClassSymbol c) { 4508 if ((c.flags() & ABSTRACT) == 0) { 4509 return true; 4510 } else { 4511 return c.members().anyMatch(anyNonAbstractOrDefaultMethod); 4512 } 4513 } 4514 4515 public static final Filter<Symbol> anyNonAbstractOrDefaultMethod = new Filter<Symbol>() { 4516 @Override 4517 public boolean accepts(Symbol s) { 4518 return s.kind == Kinds.MTH && 4519 (s.flags() & (DEFAULT | ABSTRACT)) != ABSTRACT; 4520 } 4521 }; 4522 4523 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */ 4524 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) { 4525 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) { 4526 if (types.isSameType(al.head.annotationType.type, t)) 4527 return al.head.pos(); 4528 } 4529 4530 return null; 4531 } 4532 4533 /** check if a type is a subtype of Serializable, if that is available. */ 4534 boolean isSerializable(Type t) { 4535 try { 4536 syms.serializableType.complete(); 4537 } 4538 catch (CompletionFailure e) { 4539 return false; 4540 } 4541 return types.isSubtype(t, syms.serializableType); 4542 } 4543 4544 /** Check that an appropriate serialVersionUID member is defined. */ 4545 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) { 4546 4547 // check for presence of serialVersionUID 4548 VarSymbol svuid = null; 4549 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) { 4550 if (sym.kind == VAR) { 4551 svuid = (VarSymbol)sym; 4552 break; 4553 } 4554 } 4555 4556 if (svuid == null) { 4557 log.warning(LintCategory.SERIAL, 4558 tree.pos(), "missing.SVUID", c); 4559 return; 4560 } 4561 4562 // check that it is static final 4563 if ((svuid.flags() & (STATIC | FINAL)) != 4564 (STATIC | FINAL)) 4565 log.warning(LintCategory.SERIAL, 4566 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c); 4567 4568 // check that it is long 4569 else if (!svuid.type.hasTag(LONG)) 4570 log.warning(LintCategory.SERIAL, 4571 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c); 4572 4573 // check constant 4574 else if (svuid.getConstValue() == null) 4575 log.warning(LintCategory.SERIAL, 4576 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c); 4577 } 4578 4579 private Type capture(Type type) { 4580 return types.capture(type); 4581 } 4582 4583 // <editor-fold desc="post-attribution visitor"> 4584 4585 /** 4586 * Handle missing types/symbols in an AST. This routine is useful when 4587 * the compiler has encountered some errors (which might have ended up 4588 * terminating attribution abruptly); if the compiler is used in fail-over 4589 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine 4590 * prevents NPE to be progagated during subsequent compilation steps. 4591 */ 4592 public void postAttr(JCTree tree) { 4593 new PostAttrAnalyzer().scan(tree); 4594 } 4595 4596 class PostAttrAnalyzer extends TreeScanner { 4597 4598 private void initTypeIfNeeded(JCTree that) { 4599 if (that.type == null) { 4600 if (that.hasTag(METHODDEF)) { 4601 that.type = dummyMethodType((JCMethodDecl)that); 4602 } else { 4603 that.type = syms.unknownType; 4604 } 4605 } 4606 } 4607 4608 /* Construct a dummy method type. If we have a method declaration, 4609 * and the declared return type is void, then use that return type 4610 * instead of UNKNOWN to avoid spurious error messages in lambda 4611 * bodies (see:JDK-8041704). 4612 */ 4613 private Type dummyMethodType(JCMethodDecl md) { 4614 Type restype = syms.unknownType; 4615 if (md != null && md.restype.hasTag(TYPEIDENT)) { 4616 JCPrimitiveTypeTree prim = (JCPrimitiveTypeTree)md.restype; 4617 if (prim.typetag == VOID) 4618 restype = syms.voidType; 4619 } 4620 return new MethodType(List.<Type>nil(), restype, 4621 List.<Type>nil(), syms.methodClass); 4622 } 4623 private Type dummyMethodType() { 4624 return dummyMethodType(null); 4625 } 4626 4627 @Override 4628 public void scan(JCTree tree) { 4629 if (tree == null) return; 4630 if (tree instanceof JCExpression) { 4631 initTypeIfNeeded(tree); 4632 } 4633 super.scan(tree); 4634 } 4635 4636 @Override 4637 public void visitIdent(JCIdent that) { 4638 if (that.sym == null) { 4639 that.sym = syms.unknownSymbol; 4640 } 4641 } 4642 4643 @Override 4644 public void visitSelect(JCFieldAccess that) { 4645 if (that.sym == null) { 4646 that.sym = syms.unknownSymbol; 4647 } 4648 super.visitSelect(that); 4649 } 4650 4651 @Override 4652 public void visitClassDef(JCClassDecl that) { 4653 initTypeIfNeeded(that); 4654 if (that.sym == null) { 4655 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol); 4656 } 4657 super.visitClassDef(that); 4658 } 4659 4660 @Override 4661 public void visitMethodDef(JCMethodDecl that) { 4662 initTypeIfNeeded(that); 4663 if (that.sym == null) { 4664 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol); 4665 } 4666 super.visitMethodDef(that); 4667 } 4668 4669 @Override 4670 public void visitVarDef(JCVariableDecl that) { 4671 initTypeIfNeeded(that); 4672 if (that.sym == null) { 4673 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol); 4674 that.sym.adr = 0; 4675 } 4676 super.visitVarDef(that); 4677 } 4678 4679 @Override 4680 public void visitNewClass(JCNewClass that) { 4681 if (that.constructor == null) { 4682 that.constructor = new MethodSymbol(0, names.init, 4683 dummyMethodType(), syms.noSymbol); 4684 } 4685 if (that.constructorType == null) { 4686 that.constructorType = syms.unknownType; 4687 } 4688 super.visitNewClass(that); 4689 } 4690 4691 @Override 4692 public void visitAssignop(JCAssignOp that) { 4693 if (that.operator == null) { 4694 that.operator = new OperatorSymbol(names.empty, dummyMethodType(), 4695 -1, syms.noSymbol); 4696 } 4697 super.visitAssignop(that); 4698 } 4699 4700 @Override 4701 public void visitBinary(JCBinary that) { 4702 if (that.operator == null) { 4703 that.operator = new OperatorSymbol(names.empty, dummyMethodType(), 4704 -1, syms.noSymbol); 4705 } 4706 super.visitBinary(that); 4707 } 4708 4709 @Override 4710 public void visitUnary(JCUnary that) { 4711 if (that.operator == null) { 4712 that.operator = new OperatorSymbol(names.empty, dummyMethodType(), 4713 -1, syms.noSymbol); 4714 } 4715 super.visitUnary(that); 4716 } 4717 4718 @Override 4719 public void visitLambda(JCLambda that) { 4720 super.visitLambda(that); 4721 if (that.targets == null) { 4722 that.targets = List.nil(); 4723 } 4724 } 4725 4726 @Override 4727 public void visitReference(JCMemberReference that) { 4728 super.visitReference(that); 4729 if (that.sym == null) { 4730 that.sym = new MethodSymbol(0, names.empty, dummyMethodType(), 4731 syms.noSymbol); 4732 } 4733 if (that.targets == null) { 4734 that.targets = List.nil(); 4735 } 4736 } 4737 } 4738 // </editor-fold> 4739} 4740